## Sunday, April 10, 2016

### Day 134: Estimating song length, WODB recap, Squares to form Triangles & 2-way frequency tables

Today's estimation was how long is the song Can't Buy me love by the Beatles (day 127). Most students decided the song was halfway over, so double how much time had passed. Some students added a little bit to a lot on after that. Students enjoyed listening to the 45 second music clip for the answer.

In class students investigated combinations of 3 different sized squares to form triangles. Before that we established some background knowledge. I first asked students to tell me what an acute, obtuse, and right triangle was. What made a triangle, an acute triangle? I told them to be as specific as possible. Most students understood that an acute triangle has all 3 angles less than 90 degrees. When it came to an obtuse triangle, some students thought all angles would be obtuse, but students were quick to correct that it has 1 angle that is obtuse, or greater than 90 and less than 180. I liked that some students added less than 180, a feature of obtuse angles that is sometimes forgotten. Finally, a right triangle had exactly 1 right angle that measured 90 degrees.

I then drew a square with side lengths of 5 on all sides. I asked how to find the area of it. They said do base times height or length times width, therefore 5*5 to get 25 square units. I asked if there was another way to write 5*5. They said 5 to the second power, or 5 squared. I told them that this is how we got the saying "squared" because to get the area of any square, we square the side length. I stressed that wouldn't you rather say "5 squared" rather than "5 to the second power?" It's more efficient. I asked them what it's called if you add all the sides, and they quickly said perimeter. These two concepts are mixed up frequently.

From there students used the pre-cut squares for lesson 9.2.1 in partnerships to find combinations of 2 of each type of triangle. I also asked them to find an example of a non triangle.

 A student wanted to show me how he stacked the cut out squares.
After this we did a mathography community building followed with 15 minutes to take their assessment. On Monday we will share out the data results, and construct the conjectures of what must be true about side lengths to form triangles, and what must be true to make acute, obtuse, and right triangles. Then they will practice this. On tuesday we will take notes with examples for each to solidify the concepts and do more practice. On Wednesday they will do a MARS task called Rugs as a 15 minute pre-assessment the last part of class.

I collected the 10 days of WODB warmups, and here is a good example of a student that wrote down all of her classmates ideas and did a thorough job:
 As you can see we investigated the number cubes WODB by Andrew Gael, shapes, Power Numbers, linear equations, and the terms of an expression.
 The first 5 warmups were the WODB logo, 9 16 25 43, fractions, probability spinners, and linear functions.
In accelerated we went over how to use a 2 way frequency table instead of a Venn diagram to solve a problem. They then worked on probability and then practiced it some more.
 This student did a thorough job. This class did a sequences WODB because it's part of the Algebra I curriculum.

 I had to take a picture of this one because I did not make students copy down the pictures, but she did and put the ideas on top of it. Amazingly detailed work!!
 The linear inequality graphs is unbelievable.