My son has this intense obsession with animals.  He has since he was a little kid, so most of his toys are animals.  (I am slightly embarrassed to show you the vast number of animal toys that he has, but I will tell you that most were acquired at thrift stores…)  So one day, I thought it would be fun to get them all about and sort them into different types of animals.  It was really fun way for kids to learn animal classifications!  He had his sister and cousin helping them.  They made it into a sidewalk zoo.  It was a great game for learning to sort and classify things.