In the lesson on adding and subtracting within 5, students will use five frames to add and subtract. They will also review key vocabulary terms, like sum, difference, and equal sign.

In this lesson, students will use keywords and the part-part-whole model to solve addition and subtraction word problems with 2-digit and 3-digit numbers.

In this lesson on addition and subtraction within 20, students learn how to solve addition and subtraction story problems by finding clue words. Adding three addends is also taught in this lesson.

In this lesson, students will use number lines and ten frames to solve subtraction word problems within 10.

Everybody loves Lance! But did you know he’s an avid climber? This animal ambassador is full of surprises! Learn all about North American porcupines in this week’s Creature Feature, part of our Wildlife Wednesdays series. Worksheets available for grades PreK-K and 1-2.

Students add and subtract plays on a football field to practice working with negative and positive integers on the number line.

Use this fun example to compose 10 from numbers within 10. Agent Oscar shows agents how to combine gadgets to form the gadget they need.

In this video from Odd Squad, Olive and Otto get trapped in a comic book! Their only hope is to travel to the last page and find a mysterious scientist. But how will they get from page one to page 30?

Learn about subtraction with the Odd Squad. Circles and triangles are disappearing everywhere, but why?

Olive and Otto need to add multiple small numbers together in series. There's only one thing to do: go to the Mathroom.

Oscar needs to calculate the value of an unknown number in a subtraction formula in order to feed the Odd Squad hamster.

Learn about addition, subtraction, and making amounts equal with the Odd Squad. When Ms. O and O'Donahue visit the Mathroom, she is excited to see her old friend and help with the case.

Learn about addition and subtraction in this fun clip from the Odd Squad. Otto's favorite band has a new song, "Take Away Four."

Learn about doubling numbers with the Odd Squad. While babysitting the doubled Debbies, Otto discovers something that might help Olive crack the case and find the missing double.

Olive and Otto use counters to figure out how many objects are being taken away in a visit to the Mathroom.

This task acts as a bridge between understanding place value and using strategies based on place value for addition and subtraction.

This short video and interactive assessment activity is designed to teach second graders an overview of addition (sums to 100) - word problems.

This short video and interactive assessment activity is designed to teach first graders an overview of subtraction (numbers to 100).

This video lecture serves as a review of subtraction up to the number twenty for first graders.

This task provides a context where it is appropriate for students to subtract fractions with a common denominator; it could be used for either assessment or instructional purposes.