## Borrowing from the MTBoS

I’m guessing that most of you reading this are familiar with the awkward acronym for the Math Twitter Blog-oSphere – one of the joys of tapping into this community is that they are remarkably generous about sharing ideas and resources. Today in our Geometry classes (I teach only one of the five sections we have at our school) we used an activity written by Kate Nowak (@k8nowak on twitter). It is an activity based in GeoGebra and allows the student to explore the ratio between lengths of legs in a right triangle. You can find the document we used here . I modified (very slightly) the document that Kate originally posted here. Next time I use it I will tweak it a bit. I have only twelve students in my class and chose not to explicitly team them up. They talked with their neighbors as they are usually encouraged to. However, the directions either need to be tweaked so that team references are excluded or I need to clearly team them up. I am also debating question 7. A number of students did not make the explicit leap from using the ratio they found on page 1 and using it here. I don’t necessarily want to give away too much but I may add a little prompt that they should consider the work that they have already completed. We set up a google spreadsheet and in the next couple of days I will refer to this repeatedly to show that different students working on different triangles were arriving at the same ratio. We make a big explicit deal about scale factors between similar figures. I do not think we spent enough time pointing out that scale factors within figures will also match up for similar figures. I will definitely make this more of a point of emphasis next time through my text.

I cannot thank Kate enough for sharing this activity. My students worked well and I am convinced that they will have a more solid grasp of trig ratios moving forward. As I plan out the rest of the unit I am also going to be borrowing from Sam Shah’s latest post about trig. You can find that over here.

Man – the benefits my students are reaping from people that they will never meet – such as Kate Nowak, Jennifer Silverman,  John Golden, Jed Butler, Sam Shah, Pamela Wilson, Meg Craig, and so many more – is just remarkable.

## Professional Growth in a Connected Age

I’ve been teaching for a long time now. It makes me feel old when I realize I am in my 27th year in the classroom now. I joke with my students that I have been teaching longer than any of them have been alive. When I started teaching the predominant models of professional development were the inservice days at school where the school administrators decided how we needed to grow, the weekend workshops or summer workshops that I would scramble to find funding for, or the one or two day workshops that would cause me to miss school. It’s a different world now. I know I’m preaching to the choir if you are even reading this but this world of twitter, of blogs (both writing them AND reading them), of online simulcast workshops, or improv EdCamps, the list goes on. In this day in teaching I am fully convinced that if you want feedback and you want connections to help you think about your craft and to expand your toolbox – if you really want it – there is an ocean of resources at your fingertips. Literally (since I’m typing this right now!) at your fingertips. Not all of it fits everyone. I know that I am still wrestling with the timing and pace of my twitter feed, but I think I’m getting better at it and I KNOW I’m growing as a result of it. I spent a long time reading blogs, then commenting on blogs before I felt confident enough to launch my own. I have two kids at home so I know how tight time can be, but I also know that the past two Saturdays (that I blogged about separately here and here ) where I spent a combined 16 hours out of the house were worth the time and effort. Luckily Mrs. Dardy is kind and flexible and supportive of this pursuit.

I’ve been thinking quite a bit about this, about how different my life as a teacher is in the past few years. I’ve been in regular communication with one of my former colleagues, Gayle Allen. Gayle (@GAllenTC) hired me seven years ago when my family left Florida and we landed in New jersey for a while. Gayle is a remarkable, energetic thinker and was a great boss. She and I have been engaged in a long conversation about professional growth and one of the results of this conversation is an article that got posted today over at a website called Getting Smart. I know that I am not unique in this journey, but I also know that there are still many of our colleagues who have not taken this plunge. Some because they are not interested in doing so, some because they don’t know where to start. I’m pleased to be able to give shout outs of thanks to Dan Meyer (@ddmeyer) and to Sam Shah (@samjshah) through that article and I’m pleased to be connected again (even if we are nearly 3000 miles from each other) with Gayle.

This summer will see a trip to OK to take part in TwitterMathCamp. This would not have happened if Tina Cardone (@crstn85) had not reached out to me and asked me to join in on the fun. This summer will see me finish an in-house Geometry text for our students. This project would never have happened without the encouragement and advice of Jennifer Silverman (@jensilvermath). This summer will see me work on plans to help a brand new teacher in our high school take the leap from teaching Algebra I in the middle school to teaching Honors Precalculus for the first time. All of these experiences will help me grow as a professional. 27 years at it now and I feel like I still have an awful lot to learn. I hope to be smarter this time next week about this craft than I am right now.

## Parametrics / Conics

As I have written before, we teach AP Calculus BC here as a second year Calculus course in our school. This gives me loads of time to play and explore with these students. On Monday we start up again – weather permitting – and we start with our study of parametric and polar equations. Our precalculus class does not cover either topic in great depth (a situation I hope that I can remedy starting next year) and a number of our BC kids are ones who start off in AB Calculus when they come to our school. With so many of our students coming from different parts of the world at different times in their career, we have a wide variety of experiences in the BC group. I guess this is a long-winded way of saying that I have to treat this material as if they have not encountered these ideas at all, really. I intend to spend two days in our computer lab working with building up some fluency with Desmos. I have my room set up in a sort of Harkness-style where the kids are facing each other. Being in the computer lab gives me the flexibility of having the students work with Desmos in a hands-on fashion rather than just watching me. That’s the plus. The downside is that they are working in isolation in this room. I’ll have to deal with that downside for a few days. So, I was digging through my memory bank and I remembered that the great Sam Shah had written a lovely post about introducing conics through Desmos. I downloaded his Scribd file and modified it a bit (you can see my version here) but I still need to go back and play with it a bit more. The way the file looks to me now is way too close to plagiarism – though I do give his website a nod of thanks there. I want the language and the feel to reflect my language and the way my students react.

I am making a real commitment to myself to get out of the way more in 2014. There was a lovely piece that was tweeted out by an old colleague named Gayle Allen. It was called ‘Becoming Invisible in My Classroom‘ and it has given me a renewed sense of mission here. I am also thinking of my visit to SLA last year for EduCon. I walked into a physics class and could not figure out who/where the teacher was for a few minutes. I was amazed and humbled. Need to hold on to that feeling…

So, I’ll start on Monday with a bit of leading/lecturing to set the stage. I’ll give them an assignment to play a bit with Desmos Monday night, then we hit the lab. I’ll be giving an update on how it goes. Wish me luck!

PS – I have a fun Desmos file to look at for them as well. You can see it here. It’s fun to animate the slide and see what happens.