Most kids struggle with numbers that require "carrying" or "borrowing." Friendly numbers make those problems disappear.
Cut one number in half and double the other. The answer stays the same. Example: 14 x 5 Half of 14 is 7. Double of 5 is 10. . (Much easier than 14 x 5!) Mental Math Kids Can't Resist!: Tips, Short-cut...
Making math feel like a game rather than a chore is the "secret sauce" for helping kids master numbers. When kids realize they can solve problems faster than a calculator can be turned on, their confidence skyrockets. Most kids struggle with numbers that require "carrying"