A decade ago, keeping a kid from forgetting over the summer everything he or she learned in school that year meant flash cards. Solid, white paper stock that didn't actually flash.
Now, as my math teacher husband says, kids from toddlers to tweens who need to catch up or who want to get a jump on mathematics have a number of electronic options from which to choose. And some of them do actually flash.
We've compiled a list of our favorite go-to math apps, broken down by age and interest. These worked wonders keeping my kids thinking math over the summer. Best of all, half of them feature my favorite number: zero, as in FREE. Many are available on both Apple (iOS) and Android platforms; download prices are as of June 2016.
Looking for more ways to keep your kids engaged over summer break? Check out our brand-new Summer Slide Busters Guide, offering brainy NYC activities and at-home DIY projects.