Rugrats: Time Travelers for the GBC. I got that game when I was like seven, and I STILL can't beat the first level. You're in a mine, trying to find a coin, and then go to an unspecified area. The thing is, it's like a giant maze, and doesn't tell you AT ALL where to go. Oh, and there's a time limit. And enemies, which knock you back, and take the coins (not the big coin, there are smaller coins as well) you've collected, and you have no way to fight back. And there's no minimap, to add insult to injury.
That game was made for kids? Really?