I ask students to think back to the monsters that we made and counted the perimeter of several days ago. I bring out a pair of monsters (with perimeters already written on them) and ask students to find the difference between the perimeter of 2 of the monsters. I tell them that they should think of a number sentence to express the problem and then solve their number sentence. I give students several minutes to write an equation and try to solve it.
Next I ask for a volunteer to show us how they figured out the difference between the two perimeters.
I repeat the process with 2 other sets of monster perimeters. I walk around the room to see how students are comparing the monsters. I am looking at strategies, and also if students understand what it means to compare two numbers.
Students are given a paper and pencil assessment of the uses of place value to solve 2- and 3-digit addition and subtraction problems. The questions are created to assess 2NBT A.3, B.6 and B.9.
They work independently to solve the problems. The problems include using the ten frames, expanded form, and their choice of strategies to solve the word problems.
The purpose of the assessment is to see which students need additional help in the use of place value strategies.