I would think some of the older games like asteroids, crazy climber, pacman, donkey kong, ms pacman, frogger, bubbles, joust, circus charlie, burger time, anteater, timber, zoo keeper, rootbeer tapper, portman, mario bros
Race car games- Bump n jump, Drift out, great 1000 mile rally, rally x ect.
Some killing required centipede, Mr Do, galaga, dig dug, 1941, phoenix
There are a lot more (I could have kept going) and really too many to list. Some of the games may seem a little too hard for a 3 year old but once you get them started they usually catch on pretty fast, or have a lot of fun trying
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Push them a little bit and you will be surprised how fast the learn, before you know it they'll turn 4 then 5. Just make sure to have fun and don't pigeon hole them too much