Near doubles are facts where one addend is one more than the other, like 5 + 6, 7 + 8, or 3 + 4. Students can use known doubles as a starting point: since 5 + 5 = 10, then 5 + 6 must be one more, or 11. This strategy connects to deeper understanding of number relationships.
Start with known doubles, then show how near-doubles are 'just one more.' Use visual models like ten-frames or number lines to demonstrate this relationship.
You already know your doubles facts: 1+1=2, 2+2=4, 3+3=6, 4+4=8, 5+5=10, 6+6=12, 7+7=14, 8+8=16, 9+9=18. Those facts live in your memory, ready to use. The near-doubles strategy is about using what you already know to figure out something you haven't memorized yet — by recognizing that some addition problems are just one step away from a fact you already have.
Here's how it works: "near doubles" are pairs where the two numbers are one apart, like 5 and 6, or 7 and 8. When you see 5 + 6, you can think: "I know 5 + 5 = 10. And 6 is just one more than 5, so 5 + 6 must be one more than 10, which is 11." You don't have to count from zero — you use the known doubles fact as a launching pad and take one hop. This is much faster than counting on your fingers or starting over from scratch.
Let's try a few. You know 7 + 7 = 14. So what is 7 + 8? Eight is one more than 7, so the answer is one more than 14: it's 15. What about 6 + 7? Six and seven are one apart, and you know 6 + 6 = 12, so 6 + 7 = 13. What about 4 + 5? Four plus four is 8, and five is one more than four, so 4 + 5 = 9. The pattern always works: when two numbers are one apart, use the smaller number's double and add one more.
The deeper idea here is that knowing one fact helps you find another. In math, you rarely have to start from nothing — there is almost always something nearby that you already know. Near-doubles is your first example of this kind of thinking, but it's a pattern that shows up all the way through mathematics: use what you know to reason your way to what you don't. Practicing near-doubles builds this habit of looking for "what's close to something I already know?" which is one of the most powerful tools a mathematician has.