High Quality Content by WIKIPEDIA articles! JumpStart Adventures 3rd Grade: Mystery Mountain is a personal computer game in Knowledge Adventure`s JumpStart series of educational software. As the title suggests, the game is intended to teach a third grade curriculum. This is the only version of this game created and, unusually for Knowledge Adventure, is still being sold over fifteen years after its initial release in 1996. It is currently included as the "Fundamentals" disc of JumpStart Advanced 3rd Grade.