Donkey Kong Jr. Math is an edutainment title for the NES, when Nintendo tried to appeal to the parents by releasing this game to teach children math. It didn't go well to say the least, resulting in Donkey Kong music game being cancelled, and this is the only released game that has "Education Series" label. As a game, there's little reason to play this nowdays, however I don't think it's the worst thing ever. I can see multiplayer being fun. I also think this is a case, where retroachievements has elevated my perception of this game slightly. Going for highest score in excercises can be quite challenging, almost feeling like you have to speedrun it. Of course with modern emulation technologies you can cheese it, but y'know. That being said, I'm not going to say this is a hidden gem or anything. This is still a rather basic edutainment game, of which you can find much better alternatives nowdays.