We got this puzzle as a present when Jun was 1 1/2. It was beyond her and my abilities then, but, I found it before going home to the States for Christmas last year and took it along. Junnie and Grammy and Grandpa ALL loved this puzzle. Each of the adults tried to get it away from Jun so they could figure out the patterns on some of the harder ones. Jun has even those nearly down pat now.
Basically, there are pictures with shapes cut out in them. There are 8 triangle wooden blocks that fit in the shapes. Some are very easy. One triangle per puzzle. Others are harder 7 or 8 triangles are needed to fill in the shape. I noticed on Amazon.co.jp, that KUMON has a few other puzzles too, like this.
There is no need to understand a word of Japanese to use this puzzle with your child. My Mom figured it out just fine!
I never did well on spacial tests in school, so I hope this puzzle and ones like it will give Jun a leg up in this area. Jun just enjoys the tickles she “earns” when she gets a puzzle right!