This is one of Kerr's very favorite activities! All you need are some animal flash cards- hereare some cheap ones from amazon, and a bucket of animals for your kids to match to the cards! We bought this set of animals off of amazon a few years back, and they are by far the most affordable set we have ever found! At target, these animals are $7 each! You can also use the mini zoo animals, but I like mixing the large and small ones so he can match more than one to each card! This is a wonderful activity to practice carry over by having the kids match physical items to the cards, that don't necessarily look exactly alike. It is pretty much a new spin on a puzzle that works their minds in an entirely different way. I am always on the look out for new flash cards because activities like this are always a huge hit with my kids!!