Here is one I did for my son when he was little.
We don't like the idea of giving out too much candy, etc. at Easter. (Some, fine...live a little, but no kid needs too much of that sort of thing and it is not a regular thing in our home.) What we did was assemble a jigsaw when he wasn't looking and then take a small group of pieces which will fit with each other in some way and put them in plastic eggs which we then hid. With more an one kid, this even becomes a joint/cooperative activity instead of a competitive one. The reward is the completed puzzle, which might even have a special message on it.
Instead of using Easter eggs, this can also be done "treasure hunt" style where the small pouches of pieces are hidden in places indicated on a map or to be found by clues. (This is really easy to adapt for each individual/age/level. I have a friend who hides the main present of his young teenager geocache style and makes him find it with a handheld GPS every year. lol!)
