Subtraction and Arrays

Since we learned the algorithm for subtraction I've been trying to make it as hands on and concrete as possible to really cement the process and deepen the students' understandings.  Last week we used fun bandaids when we had to break apart a number for regrouping.  But my favorite part was after solving and checking with a partner, students were asked to come to the front and teach the class how to solve their problem.  Excellent work second graders!

These two mathematicians had to regroup across a zero.
I love that they went straight to the base ten blocks to figure it out.

We have also started to learn about multiplication and how we can use arrays to make equal groups.  Here are two sweet kids in action creating a Groups of 10 class big book.