Lego City: Undercover
Developer: TT Fusion
Release Date: March 18, 2013
A lot of sandbox games can be played for a long time, but Lego City: Undercover has the additional benefit of letting you customize and modify aspects of the world with Lego bricks meaning there is literally no limit to the new things you can do in the game.
For parents looking to save themselves from buying stacks of games all year long, Lego City won't be a bad choice as it's kid-friendly and looks to have that particular form of addictive creativity that children get hooked on. It's like crack essentially, but for learning and stuff.