Rainbow Pebbles is early mathematics manipulative from edx education. 36 plastic pebbles are designed in 6 colours and 6 sizes and they have a really nice feel to them. Age restriction is 3+, but Max was really into the set. With him we practised sorting by colour and size and sequencing. And he just loved balancing pieces to build towers. Alex was more into copying designs from supplied activity cards or just making his own creatures.