Developer: Simage

Simage was a small company in Novato, California, that sold Eli’s Ladder, an educational Atari 2600 cartridge, by mail order. It drills counting, addition and subtraction for young children: each right answer sends Eli, a friendly alien, one rung up the ladder to his spaceship. There are ten levels each of addition and subtraction, untimed and timed ways to play, and apples that help count out a sum. Very few copies were sold, so it is one of the rarest 2600 cartridges.
Help Eli climb below, in your browser.