# Lesson 7 Center Day 1

Let’s use place value to identify numbers and practice adding and subtracting.

## Warm-up True or False: Compare to 100

Decide if each statement is true or false. Be prepared to explain your reasoning.

## Activity 1 Introduce Mystery Number, Three-digit Numbers

We are going to learn a new center called Mystery Number that you might have played in first grade. You will pick 3 cards and make a mystery three-digit number. Then you will give your partner clues and they will try to guess your mystery number.

## Activity 2 Centers: Choice Time

Choose a center.

Jump the Line

Mystery Number

Number Puzzles