My two-year old loves this toy! I mix up all the pieces and put them on the wrong posts and she takes great delight in putting them all back where they're supposed to go. This set is great for teaching/reinforcing colors, shapes and numbers. It's made out of sturdy wood like all the Melissa and Doug products and the pieces are easy for little hands to take off and put on.
I had reservations about ordering this because another reviewer had mentioned that the pentagons were tagged with the number 4 and the squares were tagged with the number 5. However, I ordered it anyway and was pleasantly surprised to find that they have apparently rearranged the shapes to fix this problem. On the set I received there is one circle for #1, two rectangles for #2, three triangles for #3, four squares for #4, and five pentagons for #5.
My only regret is that I didn't get this sooner. It's recommended for 2 years and up but I think with supervision it could be introduced from 12-15 months on. By the way, I ordered this with the Melissa and Doug Beginner Pattern Blocks, the Melissa and Doug Geometric Stacker, and the Lauri Pegboard. This stack and sort board and the beginner pattern blocks are definitely my daughter's overall favorites so far.