Making Sense of the Infinite in Calculus

Some of this blog post is kind of embarrassing to write, it regards an idea that I have worked with for years and I feel I should have had a better sense of it than I do. I’ll start with a conversation I had with my wizards in BC Calculus recently.

We are discussing convergence tests for series and one of the standard tests is the integral test. As Stewart presents it, at least how mrdardy presents Stewart’s presentation, we discuss an infinite series and if the integral of the function has a finite answer, then the series itself converges. Formally, what my students were told is this:

Suppose f is a continuous, positive, decreasing function on the interval [1,∞) and let the sequence a(n) = f(n). Then the infinite series ∑a(n) is convergent if and only if the improper infinite integral ∫f(x)dx is convergent. If the integral is convergent, then the series is convergent. If the integral is divergent, then the series is divergent.

 

Pretty clean and clear for a calculus statement, right? We had a nice discussion about the difference between looking at the integral which is a continuous summation versus the value of the series which only sums the natural number inputs. A question arose about how to compare the value of the integral with the value of the series. We decided, I really leaned them in this direction by thinking out loud, that the integral sum would be greater than the sum of the series since the integral also added “all that stuff between natural number inputs”. We all seemed happy with that conclusion until yesterday. My LaTex skills are lacking, so I will try this as best I can without that tool. Apologies in advance.

The series we were looking at was the infinite series of 4/(n^2+n). They quickly recognized that this could be rewritten using the method of partial fractions. We rewrote it and, by the magic of the telescoping series, we saw that the sum was 4. All good, right? Well, someone asked me to remind them how we could use the integral test to confirm convergence. We integrated the function using partial fractions and arrived at a sum of 4 ln2. Nice, the integral converged as well. Not so nice, the integral is less than 4. This violated what felt like a nice conceptualization that we had talked through a few days earlier. I sent out a quick call to twitter about why the integral test, that I had convinced myself of providing a ceiling for the sum approximation, would do this. I got a gentle reply from @dandersod reminding me that the integral is the floor for the approximation. I am pretty sure that I have known this at some point, but had constructed such a compelling Riemann approximation argument with my students that I was stumped.  I dismissed them for lunch.

One of my advisees dropped by for a quick chat. He is one of our three Differential Equations students this year. He took a look at the problem and I tried to convince him of my mistaken impression that the integral gathers up all this other area and should be an overestimate. He paused, thinking about the problem and then had a great ‘A-ha’ moment. He said, isn’t the series just the left hand Riemann approximation? Since the function is decreasing (otherwise, it wouldn’t converge!) this left-hand approximation will necessarily be an overestimate. Nice, clear reasoning. The kind of reasoning I should have had at my command when talking with my class a week or so ago. Sigh.

My Calculus kiddos are taking a test today. I get to apologize AND praise one of their colleagues on Wednesday when we revisit this ‘mystery’.

 

How Can I Communicate What I Value?

An email from a colleague a couple of days ago has my brain buzzing a bit. Here is the note he sent me:

Hey Jim, I just made a connection from our conversation this evening with an earlier conversation. It manifests mostly as a question/challenge.

You have said, and I agree, that we ought to value what we assess and assess what we value. So, if we value collegiality and collaboration amongst students, what is a fair and appropriate way to assess that? I feel like your group quizzes are part of the answer, but I also feel like there is more to it.

 

The night he sent me this email I went to twitter to see if I could get some feedback/pushback and I did in a lively conversation with Michael Pershan (@mpershan) where he questioned whether grades were the proper avenue for communicating what it is I value in class. He closed with a couple of important points:

I’ve never been happy while using grades to motivate (it flops) but your experiences might be different than mine here. +

One further thought: an assessment is a promise to a kid that we can help them improve on what we’re assessing.

Some background here might help me clear my thoughts and might help you, dear reader, understand the origins of this whole train of thought.

Years ago, I read a powerful piece through NCTM written by Dan Kennedy of the Baylor School. Dan had been an AP admin for some time and was around when some of the sea changes were happening with the AP math curriculum. He wrote a terrific piece called Assessing True Academic Success: The Next Frontier of Reform. You can find it here, it is worth a read. The quote my colleague referred to is from that article and it is a point I raise with my department when we talk about the role of assessment. I have written before about my commitment to trying to create a culture of communication and collaboration in my classroom and the colleague who wrote to me had just spent a week in my Geometry class observing my team in action. He references a habit I started just a year or two ago where I have one group quiz each term here. I know that this is a baby step, but I am still trying to figure out how to find a balance between personal responsibility for showing knowledge, the ability to work productively within a group, the meaning of a grade on a report card, the reality of what lies ahead for them, etc. etc. etc. I feel that a group quiz each term is a beginning, I hope it is not the end. So, my colleague is asking/urging/challenging me (and himself, I suspect) to really dig in and think about how to effectively communicate to my students that I value communication and collaboration. I have always reflexively felt that the clearest way to communicate to students what I value is to make sure that those stated values are transparent in the assessment process. If I tell my students that I value problem solving and process in mathematics but I then give them multiple choice tests, then they will suss out that I probably do not really believe what I say I believe. In comes Michael Pershan with his measured challenges. I have a few thoughts that are coherent enough to air out here about Michael’s comments. The first comment about grades is a real challenge. I work in a college prep day and boarding school. For better or worse (probably aspects of both) grades are a HUGE force in our school. As long as I feel I am being intellectually honest about what I communicate to my students through my grading practices, I am willing to accept Michael’s statement as a deeper, long-term truth while also accepting that, in the now, my students’ behaviors (and, hopefully) beliefs can be steered a bit by how I evaluate them. Given that, the struggle is to figure out a way that feels honest, transparent, and not too terribly subjective to incorporate the values of collaboration and communication into my grading system. I have been in too many classes where students ‘participate’ in conversation by simply echoing the opinions of others so that they can get their names on the participation roll. I do not want to clutter my class this way. I also want to recognize that there are students who do not want to, who do not feel comfortable, talking out loud in whole class conversations. Most of these students are willing and able participants in smaller group conversations.

One of the things I love most in life is the sense of synchronicity I have when I realize that what is on my mind is also on the minds of others. When I suddenly see references over and over to something that I think I just discovered. Well, I took a few minutes break from this post and saw a link to a lovely post crawl through on my twitter feed thanks to the MTBoS Blogbot. The post is called Why Do You Have Us Do Things That Aren’t For a Grade?. You can find it here. It was written by @viemath. Maybe this article will spark some important insights.

I have long told my students that their numerical average in my class simply represents the worst grade that they can earn. I tell them that a student with an 88% can be an A- student if they are good citizens, if they contribute to class, if they are largely consistent or on an upward arc. I also tell them that a student with a 90% is an A- even if that student is not such a great citizen. I kind of feel good about that stance. My thought at this point is that I will simply continue to emphasize this strongly and make a distinct point that one of the major mitigating factors in figuring out whether i need to lean on turning averages into grades is to attend to class engagement as the primary point of emphasis.

I am hoping for some bolt of wisdom…

Exploring Sequences

In Discrete math we are exploring recursive sequences and talking about how to make them explicit. When given a table and a recursive definition, my team of Discrete Math warriors has gotten pretty good at examining first differences, second differences, etc. and relating them back to the degree of an explicit formula. I recognize that some of this is rote, but sometimes skill development looks like that. It was not until I presented the following problem that I realized how rote some of the problem-solving has been. Here is the problem:

 

Suppose that Hamilton is playing at the Civic Auditorium. The auditorium has only one section for seating. The seats are arranged so that there are 60 seats in the first row, 64 seats in the second row, 68 seats in the third row, etc. So, in each successive row there are four seats more than in the previous row. There are a total of 30 rows in the auditorium.

  • How many seats are in the last row?

  • How many seats are there in the auditorium?

  • The seats are numbered consecutively from left to right, so row two starts with seat 61, row three with seat 125, etc. You purchased a ticket to the play and your seat number is 1500. What row are you in? Where in that row is your seat located?

 

So, the first part of the problem went reasonably well. They were able to recall that there are 29 steps of equal size to be taken in accounting for row size, but even this was harder than it should have been due to the reflex to create a table. I began to realize that what seems automatic to me, that we are concerned with row number and with accumulated seats, was not automatic to most of my students. They set up a column of row numbers followed by a column of row size. They then arrived at a first difference of 4 for each entry in their third column and they were off on finding a linear function. The linear function is correct for the number of seats in each row, but the rest of the problem depended on them finding an accumulated number of seats. When I set up a table and had row number followed by #of seats in that row and then the total number of seats, the inconsistence with previous visuals was a real problem. Getting my students to focus on the first and second differences in this new third column was a challenge. I know that I did not answer their concerns as clearly as I need to and I have to figure out how to better answer this. Once we established that this is a quadratic relationship we were able to find the coefficients and answer the second question. It took some convincing and looking at some smaller sums along the way, but I think we came to a genuine consensus. Switching over to the third part of the question was a giant hurdle. I did not intend for them to solve a quadratic since they would get an irrational solution. Instead, I hoped for some reasonable guess and check but it became clear that, for too many of them, the ladders of abstraction leading to this part of the problem completely clouded the problem for them. I have faith that this is an interesting question. In the spirit of full disclosure, it is important to note that this is simply a (slightly) modified form of a problem from our publisher’s test bank. What I need to think deeply about are the following questions:

  1. How much quadratic function review do I want to do to help set up a meaningful context for these recursive functions? My gut feeling was that I did not want to go into those thickets with these kids. Many of the students in this class are realizing that they can do some mathematical thinking once they removed themselves from thinking that mathematical thought only looks like equation solving.
  2. How do I balance the discrete nature of this problem with the inherently continuous point of view that students have regarding quadratic functions?
  3. How do I help my students focus on building a table of data that is clear and meaningful? How to focus more clearly and quickly on the pertinent data in the problem?
  4. How can I carefully structure a positive class discussion around one in-depth, challenging problem like this in a class where too many of the students have felt defeated by math one too many times? I feel great about the general atmosphere we have created together and I want to keep that while extending their thinking.

Sadly, I have to wait until next year to make this better.

Collaborative Classrooms

When I moved up north from sunny FLA in 2007 I made a big decision about the geography of my classroom. In my last school I had seats arranged in groups of 3 or four, I referred to them as pods and my students selected their pod mates. They usually stayed with the same group all year long and built up some real team identities centered around their pod. When I moved to my new school in 2010 I had two large conference style tables brought to my room and had students sitting in big groups of 10 each. Typically, students stayed at one of the two tables all year long, but there was a little bit of movement at times. In 2015 I moved those tables out and got moveable desks and I am back to my sets of 4 seats. However, this year I am using visibly random grouping (using Flippity and happy with it) to shake things up and encourage more of a sense of collaboration across a larger group of their classmates. I begin each week with a new seating arrangement. I have been pretty happy with most of this evolution and I am convinced that these arrangements have increased student communication over the years. However, I saw Susan Cain’s TED Talk not too long ago where she talked about introverts and the impact of all of this collaborative time on their learning and their comfort. Since seeing that talk I have had a bit of an internal struggle about how to try to compensate for the fact that not everyone wants to talk as they learn. Not everyone is comfortable thinking out loud before they have come to some sort of a clean conclusion. Not everyone thinks at the same pace. Luckily for me, Brian Miller (@TheMillerMath) wrote a blog post that has come to the rescue for me with ideas about how to address some of these fears. Brian wrote about a great idea for balancing the principles at hand that seem to be in competition with each other. His post is over at http://www.mrmillermath.com/2017/01/30/alone-time-in-a-collaborative-classroom/ and I strongly encourage you to read it if you have been thinking about some of these conflicts.

Our school is moving to a new schedule next year where we will have five class meetings in each seven school day stretch with one class at 90 minutes and the other four meeting for 50 minutes. I think that these longer spans of time together (currently, the majority of our class times are 45 with a handful of 40 and a handful of 50 based on assembly schedules, etc.) will work beautifully with the ideas that Brian laid out. I am on the fence about the nature of how I want to deal with the earbud/headphone question. I like the idea that Brian has but I am not sure about endorsing any type of paid music services explicitly with my students. I know that almost all of my students come equipped with earbuds and mobile devices everyday (probably a higher percentage than those that come equipped with a writing device to class each day!) so that is not a hurdle at all. I have announced a group quiz for next Wednesday and I know that I want to have at least one day before then where I explicitly have ‘alone time’ for thoughts before reconvening our pod conversations. I am debating whether I need to physically separate seats for this alone time or whether that is too much time and interruption. I’ll be writing about how it goes.

Communication Breakdown (Rethinking Assessment Ideas)

My first post of 2017, good golly where did January go?!?

Our school uses an LMS through FinalSite, a company that manages our school home pages. It is a pretty typical looking LMS. I populate each class with my students so that when they log on to their student portal they see each class they are in (as long as their teacher uses the LMS) and they can see calendars, they can download assignments, they see their HW and upcoming responsibilities, etc. My hope is that students check in pretty regularly (daily is a pipe dream, I fear) at least on Sunday night to scope out their upcoming week. In addition to populating this calendar – usually about a week in advance, but I sometimes lag a touch, I keep a spot on one of my side chalkboards where i highlight upcoming highlights. I lagged on that recently as well. As I hinted earlier, January has been a bit of a blur for reasons I cannot pinpoint. Anyway, last Monday I had a rare Monday test scheduled for my AP Calculus BC gang. Their class met right after lunch and a couple of students came in during lunch and asked if the rumor that they heard was true. The rumor they were referring to was a rumor that they had a test that day. I mentioned that this had been on their calendar for well over a week and confirmed that, yes, this ‘rumor’ was true. Kids got on their phones to notify classmates and they frantically started flipping through their text book.

I kept my calm and I assured them that they would be fine. they had been doing their work (I said optimistically) and that last minute cramming rarely has much positive impact. Most of the class performed reasonably well – one perfect score and one student who only missed one point out of a group of fourteen – but the average was lower than usual and one student in particular was way off of his usual mark. The frustration got me thinking about a number of things and I want to use this space to think out loud about these issues.

First, I worry about communication in this increasingly digital environment. I used to print off weekly calendars and hand them out at the beginning of each week. Some kids would lose them, some would carefully put them in their folders, some would cram them in their backpack never to be seen again. Mostly, kids seemed to know what was coming up or at least kept it a bit of a secret when they were surprised by an assignment or an assessment. Now, I print almost nothing. I post on the LMS. I keep the reminder chalkboard. I send out email reminders through the LMS. I send some occasional emails from my school account with attachments for notes or suggested extra work. I hear repeatedly from students who did not know I had sent an email or that I had posted to the LMS. This makes me wonder how much of the blame lies on me for moving away from printed reminders. I mean, if 14 out of 14 students did not know that there was a test on Monday then part of the blame falls on my shoulders. But, and this is important, something is odd in the student culture around my class if 14 out of 14 students failed to register this fact in a planner or take a look ahead at their upcoming week before reporting to school on Monday. I do want to take a moment here to compliment my students in their reaction to this event. Not a single one complained about unfairness, not a single one said to me that this was my fault, and when they received their grades back not a single student voiced their unhappiness about the situation. It would have been so so easy to point the finger at me and none of them did. This is a credit to their character and willingness to take responsibility. A number of them did ask to take advantage of my policy for reassessing, but no more than usual really.

So, I am questioning my role in communication and the avenues I choose to take advantage of. The other question this raises for me is my attitude about announcements for assessment. I know that many of my colleagues, both in my building and out in the world, have as part of their practice unannounced assessments. I have never done this and it is mostly because I find myself overly sensitive to charges of increasing/causing student stress. I always make sure that there are at least three school days between announcing and administering an assessment. In the case of major unit tests, I want to have at least one weekend between announcing and administering the test. But this incident has me questioning this commitment. Am I seeing a more true reading of student mastery of material if I check in periodically when they do not know that I will do so? Am I bypassing the stress of test and quiz preparation if I just drop a quiz or test in their lap when they show up for class? How do I setup a situation where an unannounced assessment is not such a big deal for the student?

As always, I am seeking wisdom here. If you have made a practice of unannounced assessments, how do you handle that? How do the students respond? If not, is your reasoning similar to mine? How do you communicate calendars to your students? Teachers here use either our school LMS, Google Classroom, Facebook, or old fashioned paper. What are the habits at your school? What really works? Drop me a line here or over one twitter where I remain @mrdardy

Trying to Understand what my Students Understand

Starting to think about school again and this question has been clanging around in my brain. On my last test for my AP Calculus BC kiddos I included the following question: screen-shot-2016-12-29-at-11-33-34-am

My BC gang absolutely nailed this question. Almost every single one cited concavity for part b noting that a function with positive slope AND positive concavity will increase at an increasing rate while the tangent line increases at a constant rate. So, moving to the right of the point of tangency means that the function has pulled away from the tangent line. They almost uniformly used the language I just used with slight tweaks and maybe a little less detail since they were operating under time constraints. I was proud of them for such detailed answers to an important principle of graph analysis. However, after the happiness faded there was a nagging concern that arose. I worry that they are SO good at citing this language that perhaps they are simply responding to a familiar prompt. I am not here claiming that these talented students do not understand this principle. I am here claiming that I am concerned that I have ‘trained’ them too well in responding to certain prompts, that I have enabled them to simply repeat a claim that I have made convincingly in their presence. I want to do some deep thinking about how I can circle back to this idea and ask this question in a form that is similar enough that it is clear what I am asking, but different enough that my students will have to say something different to betray their understanding. I would love any advice on how to continue to poke at/probe how deeply my students understand this concept. Any clever ideas out there? Drop a line into the comments section or tweet me over @mrdardy

 

My Students are Making Some Smart Guesses

On Friday in Geometry we were continuing our conversation about triangle centers and I asked my students to find the point where medians coincide in a scalene triangle. There is a good amount of algebraic detail in these problems but my students were doing a nice job pushing through this problem. After finding the centroid, I asked them to form a new triangle from the three midpoints we needed when considering medians. We found the perimeter of the original triangle and I asked also for the perimeter of the triangle formed by the midpoints. One of my students theorized that the new triangle would have one-fourth the perimeter of the original triangle. I asked the other students to quiet for a moment to hear this guess. Before asking GeoGebra to check his answer he quickly corrected himself and said he was thinking about area, not perimeter. A beautiful realization on his part that this triangle formed by midpoints would divide the original triangle into four equal areas. Just as we were congratulating him for this guess another students asked about equilateral triangles. He wondered aloud whether the midpoint triangle in an equilateral triangle would form four equilateral triangles. I realized he was asking whether the triangles formed in the scalene we were looking at were also congruent, not just equal in area. A quick question from me confirmed my guess so we drew our attention again to the GeoGebra sketch we had up. He was able to identify where the congruent angles were that allowed us to prove congruence for the triangles.

This conversation was a wonderful way to end our day on Friday. I am delighted that my students are comfortable enough to make these guesses out loud and even more delighted that they are making such good guesses right now. I pointed out how helpful it is to play with GeoGebra to check these guesses and I hope (I hope hope hope!) that some of my students are making a habit of this.

A Delightful Conversation

Last week in my Geometry class we had a fantastic conversation about a homework problem. Here is the problem in question –

screen-shot-2016-12-06-at-3-56-52-pm

 

I wish that I could take credit for having written this, but I am certain that I ‘borrowed’ it from somewhere. Likely from the fantastic resources shared with me by Carmel Schettino (@SchettinoPBL)

So, this is the kind of problem that I expect only a minority of my students to navigate successfully on their own, but I am convinced that almost all of them will benefit from thinking about a problem like this one, from a little active struggle along the way. I KNEW that this would be asked in class if anyone took the time to do the HW I assigned, so I was pleased that it came up. I started by telling my students that I LOVE this problem and asked them if they could guess why. One student said ‘Because it’s so hard’. I laughed that off and said, yes it is hard but I love it because it ties together a bunch of important ideas. Off we went on solving this. I started by asking a couple of questions that probably seemed a bit irrelevant at first. I asked why they knew that the y-intercept was (0, 3) and that the x-intercept was (4, 0). Before they could answer I made sure to mention that they knew this without looking at the graph. We eventually arrived at the realization that we know whether a point is on the line or not by looking at the equation itself. If a point makes the equation true, then that point is on the line. If not, then not. This is the kind of thing that I think my students know but being reminded regularly sure does help reinforce it. I hope! So, I thought I had set the hook here for the rest of the problem. We talked about what we know about squares and we talked about how to identify points on the square without knowing their real coordinates. We got a little lazy, and I was okay with that,by calling the bottom right corner (x, 0) and the top left corner (0, y). This gave us no choice but to call the top right corner of the box (x, y). At this point I paused and asked them to remind me what needs to be true about points on a line. Then I asked them to remind me of what we know about a square, therefore what we know about x and y for that mystery point (x, y). It wasn’t easy to get everyone to agree with our conclusions, but I think we got there. We agreed that the x and the y had to equal each other. We agreed that the y coordinate had a definition based on x. We agreed that this was an equation we could solve even though it was not a bunch of fun to solve it. After all of this work it felt like the problem should be done, students were pretty sad to realize it wasn’t. We still had a conclusion to make about the triangles created. One of my students was pretty insistent that they needed to be congruent because their angles had to match up. This was not the time to launch into a conversation about similarity and I decided it was not the time to talk about the restrictions of AAA conclusions between triangles. We have talked about equilateral triangles of different sizes and we are (mostly) okay with that, but I felt that that conversation would be a diversion here. Instead, we kept at the calculating and we looked at side lengths. Once we agreed that they were not congruent, I pointed to the slope of the line and talked about the fact that his instinct was foiled by the fact that x and y lengths were not changing at the same rate. The whole conversation took quite some time, might have been 15 minutes by the time the whole thing was done, but I felt that we had done some important heavy lifting.

If you recognize the above problem as your own, feel free to claim it and let me know. Know in advance that I am very grateful for such a rich problem to tie together ideas of distances, slopes, line equations, properties of squares, and triangle congruencies all into one tidy package!

 

The Decisions We Make – A Postscript

Thank you thank you thank you, John Golden. John commented on my last blog post and gave me some important wisdom regarding my frustration with my own decisions and the decisions that my students had made last week. As expected, the quizzes were subpar. In the class where I had chosen not to explain the permutation notation I made the following grading decision. I graded the last problem as if it were a 10 point problem as advertised. However, when calculating their grade, I counted it as a 5 point problem. So, the students who had learned the notation earned some bonus points while those who had not were not stung quite as severely. Not a perfect solution, but it did open the door to a public conversation about my frustration and about how we might avoid their frustration AND my frustration moving forward. Don’t know yet how that will sink in, but at least it was received as a good will gesture on my part and no one complained out loud that it was unreasonable for me to have expected them to read that definition. We’ll see what happens in the next week or so as we have two more opportunities for showing some learning here.

The Decisions We Make…

I have two sections of Discrete Math this year, one in the morning and one right after lunch. During the fall term, each of these sections had 7 students. We all sat at a single group of desks together and had some great conversations. A number of the students have spoken to me about how much they enjoy this atmosphere. It does not work for everyone of course, some students prefer not to have the expectation of participation, they would prefer to quietly observe and have more time to think before speaking. Our school is on a trimester schedule and this Discrete course is set up as a trimester course where students can move in or out and not have the demands of previous knowledge from this course. So, I have done some thinking about how to make this course modular. One of my sections expanded from 7 students to 16 this term and we are in the process of figuring each other out and how this new group will mesh. One of the students who has been in the class the whole year commented that class seems more quiet this past week. Interesting that more than doubling the size of the class has resulted in a quieter atmosphere…

All of the above is just to sort of set up what our week together was. We started a probability unit this week and so far all of our energy has been spent on counting techniques. When does or matter? When does and matter? What is the difference between them? What is the deal with that ! function anyways? When can we tell whether replacement matters? These are the kinds of conversations we have been having and I have had in-class activities for us to work on together while I have been asking them to do some reading and some HW on their own outside of class. The great Wendy Menard (@wmukluk) shared some fantastic resources that one of her colleagues shared. She was also kind enough to spend some time on the phone last weekend to serve as a sounding board. One of the decisions I made was not to spend much time emphasizing notation together in class. For example, our text explains permutation notation pretty cleanly, points out that our calculator writes 10P4 while you might also see P(10,4). It clearly shows that this calculation is 10!/(10-4)! while also introducing this notation in more general form of P(n,r). In class we had a number of examples of drawing some subset of members from a group, so I thought that the text’s approach and our class approach would support each other. I also figured that any students flummoxed by the text notation would ask me in class what the deal was. So, the first HW question on Wednesday night was this in fact – Which is equivalent to P(10,4), 10!/4! or 10!/6! ? We had a quiz scheduled for Friday and on one of the questions I gave the students the numerical value of P(26,3) and asked for an explanation of how to get that answer. On Thursday I had a couple of review problems thrown together from the textbook author’s supplemental test bank. I planned on starting class by fielding any HW questions then turning them loose to work on the review problems. In my morning class I projected their HW from Wednesday night and had the first HW question on the board. Not one student knew what P(10,4) meant. They asked whether that was a point on the plane. I have to assume that they did not do the reading or the HW on their own. I quickly untangled the notation, pointed out how it matched some other conversations we had and then gave them their review sheets to work on. That was my morning class of 7 students. After lunch I had the book projected with the first HW question. Not one student in that class knew what P(10,4) meant. I decided to remark on the importance of doing the reading and the HW and then just gave them their review sheets and sat down.

One student came by on Friday morning during my free time to ask me a question about the notation and she remarked that it was clear I was disappointed (annoyed?) that no one had done the HW. She wanted to make sure she understood that notation. Each class on Friday began with me answering questions before the quiz and I do not recall anyone in either class directly asking me to revisit the P(n,r) notation at all. I have not graded the quizzes yet but I know that there were a number of students in my second class that either left the question about P(26,3) blank or simply wrote something to stumble into extra credit. A number called me over to ask about it and I said this was something they needed to know. I do not remember my morning class as clearly, they may have been in a similar boat.

So, as I think about this I realize that I made two very different decisions with my two groups of students and I am not happy about either of them. In one class I came to their rescue and explained something that they clearly could have come to terms with – in some way – on their own. In the other class I let my annoyance take over and I did not address the question at hand. I also realize that my students, especially those in my second class had two decisions to make. On Thursday night, after seeing my disappointment/frustration they could have gone back to their reading and either understood it themselves or they could have checked in with me during review on Friday. It is clear that a number of them did not do that. So I am faced with yet another decision when I grade what are likely to be disappointing papers. I feel that I want to get across a pretty clear message about responsibility but I also need to recognize my responsibility here. It is reasonable, I think, to see my role as someone who expands the conversation from the text, not as someone here to simply recite what the text already explains. But I also recognize that I have 9 students who are new to our class and all of them are new to me as a teacher. If they are used to teachers making sure that every question in their text is also addressed in class then my idea about my role might be a bit of a shock and I did not spend much time together on Monday explaining this about myself. However, I also have 14 students who were with me all fall and it is pretty clear that none (or very few) of them did the reading and the HW either.

I am not happy with myself that I let my annoyance get in the way of clear thinking. I am also not happy that I was not more clear with my morning class about my disappointment that none of them had done what I asked. I am not happy that so many students did not do the reading or the HW. I AM happy that I had a student come by and clarify the question for herself while also recognizing that she should have done so on Wednesday night. I feel that including the question when I compute the grade will likely have a pretty significant impact on many grades as it was one of four questions on the assignment. I also feel that it is a reasonable question to ask, but it relies on notation that I did not explicitly present.

I have been reading a number of the DITLife blog posts and there is a constant reminder about the number of decisions that we make on the fly everyday. These are complicated decisions and I know that I hope that I make them clearly. Here is a case where I think I was probably not as clear thinking as I should have been and I will likely need to make a decision about grading that will, luckily, not have to made on the fly. I have a bunch of new students who are only one week into their experience with me. I want it to be a good experience where they grow as scholars. I need to think carefully about how I respond to this disappointment – in my own behavior AND in the decisions they made.