Addition with missing numbers - 1st grade/Kindergarten math lesson
An introduction or beginner lesson on addition problems with a missing number - also called "missing addend problems".
For example, we consider the problem 1 + ___ = 4, but since children tend to confuse this with 1 + 4, I start out by placing the TOTAL at the top of the visual model (dots on die faces). So, it reads kind of like:
4 1 + __
This positioning is to help children understand better the concept, and not to get a misconception that it means 1 + 4.
From that we then transition to the regular way to write the addition horizontally, such as ___ + 2 = 3.
Lastly in the lesson we even drop the visual model of dots — by this time the children can probably think the answers and get them correct!
This lesson is meant for early 1st grade or kindergarten. I use very small numbers (from 0 to 5) so that even young children can understand the idea.
If you cannot see the video above, click here for an alternative video player.
See also
Addition facts — online practice (includes an option for missing number additions)
Mental math trick with nine and eight
Math Mammoth Grade 1 curriculum