Beautiful sets of natural tree blocks designed for children to learn mathematics. The set includes 30 wooden tree blocks from 1 cm to 10 cm. The set also comes with a natural wooden ruler for the player to identify the size of each block. Bring nature into the classroom and reinforce key maths concepts at the same time! A great set to practice with basic number sense, addition and subtraction, and fractions.The set is conveniently housed in a cotton bag.All Qtoys products are made of plantation timber using non-toxic, child safe materials.This set contains recycled Lychee wood blocks. The dimension of the blocks can be various.