To market the Famicom in mid-80's America, when video game had become a dirty word to retailers, Nintendo branded it an "Entertainment System." Advertising strongly emphasized the R.O.B. and Light Gun. It wasn't a video game system, it was a fancy robot and video gun toy! Which also happened to play video games. This is also why they redesigned it so that the cartridge went into a hidden slot, so that it looked like a VCR instead of an Atari VCS. Similarly, Donkey Kong Jr. Math was supposed to prove the NES could also be educational. All "Black Box" games were divided into series, but DK Jr. Math ended up being the sole title in the "Education Series"! However, it wasn't Nintendo's only foray into educational gaming. In 1994, they released five educational titles starring Mario for the Super Nintendo, two of which also appeared on the NES ( Mario Is Missing! and Mario's Time Machine ). The main game of DK Jr. Math ("Calculate...