Not exactly AI, but the Processing language has a 'flocking' tutorial: https://processing.org/examples/flocking.html. There's also a version in ProcessingJS: http://processingjs.org/learning/topic/flocking/

And, from HN a few days ago, Red Blog games has some awesome, in-depth explanations of game-related programming: http://www.redblobgames.com/pathfinding/tower-defense/