Learning to make tens is, hands down, the most important addition skill your child will learn in the early grades.  Here’s the deal: your girl has one hundred and twenty-one addition facts to memorize—a gargantuan task to a second grader (who will then have to move on to 121 subtraction facts, then 144 multiplication facts…!! Ah, but what if learning math facts didn’t have to be an endless to-do list