## If you teach trig, you need this post.

The reason you need this post is because Math Teacher Mambo has unlocked the secret to teaching radians so kids will understand.  YES IT IS TRUE. She posted this fabulous idea on cutting out radian pieces to use, like this:

Image from mathteachermambo.blogspot.com

How can I describe using them in class?  Well…

Exhibit A:  After two days of working with both, I informally polled all three classes about whether they prefer radians or degrees.  At least 25 – 50% raised their hands for radians, and many of them said it didn’t matter to them.  That’s right, a class where kids prefer or at least do not actively dislike radians.

Exhibit B: In one of my classes, after the poll, I told them I was so excited because this was a new way of teaching it and it actually worked.  One of the students asked, “so how in the world did you teach it before?” “We just thought about it.”  Their reaction:

Exhibit C: After that reaction, another student said that they were great to start with, but then after a while they didn’t even need them. Woohoo!

Since I use NoteTakerMakers® instead of INB, I modified my NTM from last year to accommodate Shireen’s circle files:

.doc file

We started with degrees. By “bow-tie triangle” I mean reference angle (we had done trig values at a point the day before and practiced drawing our bowtie) and by “type” I tell them short, medium, or tall.  We did the first five together and then I sent them on their way.  Yes, with greater than 360 and negative angles, which was great because everyone had a different way of thinking about where they were.

Ok, just so I’m not kicked out of the #MTBoS, I would love to do a radians activity where we discover what they are, and that one radian is the same for every circle, and it takes 2pi of them to go around, lalala discovery learning, but I have 13 class periods to go from 0 to translating sine and cosine graphs, so I showed them a quick animation from Sam and pi, 2pi, pi/2 and 3pi/2 using Math Teacher Mambo’s empinadas analogy. (except with quesadillas because our Moe’s actually asks if you want them cut in half or fourths). We had just enough time at the end of class to cut out radians out, label them, and put them in a pocket (hint: Give each student a third of a piece of paper. Fold strip into thirds. Tape two sides and you got a pocket with flap.  You can even tape it down to the NTM between the two circles, but it does over lap the chart a bit.  I could probably make it pretty so it doesn’t, but I didn’t.)

The next day we talked about the radian examples at the bottom of the NTM.  After the examples I asked them about what type of triangle we will have with denominator 6, 4, 3, and 2. I think next year, I’ll have them cut out the pieces like this:

Because lining up 7 or 11(!) of the wedges was time consuming and easy to land on the wrong space.  Plus hopefully this might help them think, “is this more than a whole quesadila?” when they are deciding which pieces to use.