We bought these to have fun creating pictures and patterns as part of a fairly informal approach to Early Years "maths". My four year old made some lovely patterns with them and appreciated the bright colours, my 6 year old did pretty much the same but we talked more about which shapes fitted together and why. We also bought the pattern "cards" with pictures to replicate, but these on their own are great and you don't have to be too prescriptive in what the kids do with them. They are made of fairly solid-feeling plastic, not too flimsy and I think they will last us a fair few years.