Algebra wrapped up solving systems by graphing today and moved on to substitution. I found an awesome intro activity over at Fawn’s 180 blog.

The first time through, I didn’t give students enough time to chew on the problem. But, for the rest of the day I gave them 20-25 minutes to work on it in small groups. A lot of students were stumped but no one was unable to at least have a start on the problem. I heard a lot of satisfying sighs of relief today after students solved the problem.

With time students came up with a lot of different solutions, I challenged all them and it was a great activity in developing reasoning.

Here are two example of student work

Several students started by assigning values certain animals and set up a system of equations ISH approach. It was fun hearing their reasoning of how they reached a solution.

The second example lends itself into a smooth transition for a conversation about substitution.

Great day today!