Lesson: Adding by Counting On: Numbers up to 20 Mathematics • 1st Grade
In this lesson, we will learn how to add within 20 by counting on from one of the numbers.
To find 8 plus 4, we can start at 8 and count forward 4.
Finish counting forward to find the answer to 8 plus 4.
Mia put her counter on 11 then moved it forward 3 spaces.
Sophia holds up 3 fingers and starts counting up, putting up one finger at a time. She stops when she is holding up 8 fingers.
Was she adding or subtracting?
Pick the number sentence that matches what she did.