Doubles are facts where both addends are the same: 3 + 3 = 6, 4 + 4 = 8, etc. Near doubles are one more: 3 + 4 = 7 (3 + 3 + 1). Doubles are easy to remember and teach, and near doubles follow quickly. These form anchors for fluency.
Use objects to show doubles physically (two groups of 3), then visually, then from memory. Use rhymes or songs for doubles (2 + 2 = 4, etc.). Introduce near doubles only after doubles are solid.
You already know how to add numbers within 20, and you've worked with number bonds — the pairs of numbers that make a target sum. Now we're going to use those skills to build a shortcut that will make adding faster and easier.
Doubles are addition facts where both numbers are the same: 1 + 1, 2 + 2, 3 + 3, all the way up to 10 + 10. These are special because our brains find them easier to remember than most other facts. Think about 4 + 4 — you can picture two groups of four objects sitting side by side, perfectly matched. That symmetry helps the answer stick. Learning your doubles is like memorizing a short list of rhymes: 2 + 2 = 4, 3 + 3 = 6, 4 + 4 = 8, 5 + 5 = 10, 6 + 6 = 12. Say them a few times and they start to feel automatic.
Near doubles are what happens when you add two numbers that are one apart: 3 + 4, 5 + 6, 7 + 8. These might look harder at first, but here's the trick — you already know the double, so you just add one more. 3 + 4 is the same as 3 + 3 + 1. You know 3 + 3 = 6, so 3 + 4 = 7. 5 + 6 is the same as 5 + 5 + 1 = 11. The near double "borrows" from the double you already know. Instead of adding two different numbers from scratch, you're just adding 1 to something you've already memorized.
Think of it like stairs. Doubles land on every other step: 2, 4, 6, 8, 10, 12... Near doubles are the steps in between — always just one step up from the double below. Once you have doubles solid in your memory, near doubles are easy to figure out in your head without counting on your fingers. This is what mathematicians call a strategy — a smart shortcut that uses what you already know to figure out what you don't yet know automatically. Practice the doubles until they feel instant, and the near doubles will follow naturally.