Students put all of their addition and subtraction skills together to solve equations. In this lesson, students put all of their addition and subtraction skills together to solve equations. Julia ...

Match fun story problems with the correct addition or subtraction expression. Join Mrs. Gray for number talk with the Counting Buddy Junior. Then get ready to match fun story problems with the correct ...

Here is a part-whole model. Sometimes the model is rotated. It looks different, but it still has two parts and a whole. We can use this model to help us solve problems. We can put 4 things in one of ...

Fact families are groups of numbers that have a relationship to each other. For each pair of addition facts, there are also two subtraction facts in the same family. Here is a fact family using the ...

Jackson Ryan was CNET's science editor, and a multiple award-winning one at that. Earlier, he'd been a scientist, but he realized he wasn't very happy sitting at a lab bench all day. Science writing, ...