Tower defense games

Here's how it works: a line of little invaders moves along a path, and you have to stop them before they reach your castle, your garden or your base. To do that, you set up towers, traps or guards in the right places, then upgrade them from wave to wave. No realistic violence: the intruders are pushed back, slowed down or put to sleep. Planning, managing resources, studying the terrain: spotting the bend where your best defense should go changes everything. These games suit kids from about 6 or 7. Lost a wave? By looking back at where your defenses were placed, you quickly see what was missing.