## Tuesday, November 3, 2015

### Day 43: FAL: Building and Solving Equations Day 1 & Triangles and Pythagorean Theorem Review on whiteboards

Today's estimation was estimating Ms. Fawn Nguyen's height, when she is standing on a chair next to Mr. Stadel. Also, it was cool to talk about how it's pronounced "WIN" but spelled "Nguyen." This threw off a lot of students. I liked when students estimated the total height, knowing it was higher than Mr. Stadel's, and then subtracting their estimate of the chair's height.

Students already completed a pre-assessment that I took a look at, and started with whiteboards on the FAL on building equations. You start with x=6, and write x+2=8 below it. How do we know the answer? How was the second equation built from the solution? They then came up with examples and then were challenged to make it a 2 step equation with 2 different operations.

Then they analyzed Amy and Laura's work. This produced some interesting reactions. I had to prod students by asking them how do you know Laura's equations are right? They substituted in the solution and realized something went wrong. They then analyzed it further. Then students solved Amy's built equations in white boards. We then went over it.

The mistake in Laura's equation (sample student work) was they added 3 to -2, instead of to the whole term (x-2/4). If it becomes (x+1/4) you are actually adding 3/4 to the left side.
Then students told me you had to put parentheses around the whole left side to show it's all being multiplied by 5.

Here's Abhishek's quote I wrote on the board. Instead of giving his partner answers and moving on, he asked his partner to notice the difference between x=6 and x+2=8. It was a great moment that showed patience, and I had to write it on the board. Also, it helped his partner understand.

In accelerated, I reviewed on whiteboards with the students. I gave them 3 side lengths and said do two things: prove if it is or isn't a triangle. If it is one, tell me what type. I would walk around and say yes or no, if yes, turn it over, if no, find your mistake. They also practiced finding the missing hypotenuse and also a missing leg of a right triangle. They then worked on a problem of a triangle on the coordinate plane with a leg that had an irrational side length.