First grade

Second grade

Third grade

Fourth grade

fifth grade

Second Grade

2-Digit Numbers

problem 7: Who has the cleanest car?

Third Grade

2-Digit Numbers

problem 7: Who has the cleanest car?

3-Digit Numbers

problem 14: How big is our harmful gas? (using bar graphs)

FOURTH GRADE

3-Digit Numbers

problem 5: Is our air getting cleaner? 

problem 14: How big is our harmful gas? (using bar graphs)

4-Digit Numbers

problem 1: Our path to cleaner air 

Decimal Numbers

problem 5: Is our air getting cleaner? 

Fifth Grade

4-Digit Numbers

problem 1: Our path to cleaner air 

Decimal Numbers

problem 5: Is our air getting cleaner?