This 25 block set of color cubes from Froebel USA® is a classic toy where each block has 4 sides with solid colors (red, white, blue and yellow) and 2 sides divided diagonally between red/white and yellow/blue, allowing millions of creative design possibilities. Introduced in the 1920's and often used by psychologists to test critical thinking skills, this toy will improve a child's visual/spatial reasoning while providing hours of fun. Winner of the 2003 Creative Child Magazine Seal of Excellence. Sturdy wood tray and pattern sheet included. Made in the China. Blocks are 30mm cubed. Non-toxic colors. For ages 3+.