AI Tutor
Imagine you have 13 stickers, and 8 of them are shiny stars. How many stickers are not stars?
Counting backward 8 times is slow and tricky, but you can turn this subtraction problem into an addition puzzle instead!
How can adding help us take away?

The Think-Addition Secret

Every subtraction problem has a whole (the total) and two parts. When one part is missing, we call it a missing addend.
To solve 13−8=?13 - 8 = \text{?}, flip your thinking around and ask: 8 plus what number equals 13?
Addition and subtraction are opposites, so they share the exact same number families. If you know how to build a number, you know how to break it apart!
How do we find that missing number fast?

Friendly Ten Jump

Let's solve 14−9=?14 - 9 = \text{?} by thinking: 9+?=149 + \text{?} = 14.
Start at 9 and jump up to the friendly number 10 (that is 1 hop). Then jump from 10 to 14 (that is 4 more hops). Put the hops together: 1+4=51 + 4 = 5!