Another for the kiddies.
Sound/Music: The music really ain't too bad, somewhat catchy at times but not something I'd always listen to, hah. There's really no sound except blips and beeps, the only sound that plays is during the Grover game pretty much.
Difficulty: Don't even need to bother with that. It's a game that teaches you basic math and shapes, no challenge.
Gameplay: Well there was a series of games made for the NES that were specifically for children (Donkey Kong Jr. Math, Mario Is Missing, etc) and this is one of a varity of Sesame Street games made. This teaches you shapes, and some math such as sums, subtraction and so on. The whole shape idea is mostly just matching them. Simple.
Controls: They are a bit whacky, things seem out of order but it hardly takes any time to get used to it.
Overall: Unless you have little kids and think this would be a cool gift for them, this is simply just a collector's item. Nothing special.