The ninja is controlled by holding down the "D" key to move right, "A" key to move left, "space" to jump/continue, and the "E" key to use the ninja's special ability (if applicable to the level). The current level's objective is displayed on top of the physics panel and you have 3 lives to achieve the goal by first solving the given problem with the information given and then by testing your answer visually by moving the ninja. NOTE: The ninja doesn't move at a constant velocity when in contact with ground and instead accelerates. Also, the distance displayed near the ninja is the X displacement to the very center of the target.