So far, it's been a big hit! Crazy Bug successfully learned to tell time in two days! The addition chapter was a little slow for her, and she's spending plenty of time practicing her facts on Xtra math, so I let her test out of that chapter. (Testing out is when you let a child take the end of unit test before studying the material. If the child can demonstrate mastery, he is able to skip the unit and move on or do enrichment work.)
We've also been spending plenty of family time playing the addition and subtraction games suggested in the curriculum. They're super easy to create if you just have a deck of cards and a couple of dice on hand. We've also been playing Smath, a Scrabble-like math game I found at a yard sale. You could also try the vintage math game Quizmo if you can get your hands on a copy.