Threezies is a great family card game for kids to adults.
The goal of Threezies is to gain the fewest amount of points over the course of several rounds. Arrange your cards into groups of "3" to discard your hand and go out. As the rounds progress, more cards are added, making the game progressively more complex!
See gameplay video: http://www.youtube.com/watch?v=g2WJ5sMUXP4&feature=youtu.be