Marbles was a traditional Easter game in granny's day: the skill is in the way you hold and flick your taw (the throwing marble), pinging the others out of the way. Luckily, flicking a taw uses the same thumb muscles as a Game Boy, so today's kids have a real advantage.
The action is smooth and firm: place a marble in the crook of your forefinger with your knuckle resting on the ground. Position your thumb comfortably behind it and flick with as much force as needed. Here are a couple of games to get started (you can buy marbles on www.houseofmarbles.co.uk).
Draw two concentric circles with chalk on the ground, about 2m and 30cm in diameter. Each player puts 10 marbles into the inner circle. Players then take it in turns to shoot a taw from the edge of the outer circle at the central marbles. The shooter keeps any marbles pushed out of the inner ring by their taw, and gets to shoot again from where the taw landed. Their turn ends when a taw fails to push any marbles out of the circle. The next player then shoots their taw, either at the central marbles, or at the other player's taw. It they hit the taw, they are paid one marble by the taw's owner, and have another go. The game continues in this way until all marbles are collected.
Draw a ring 30cm in diameter on the ground. Everyone who plays puts the same number of marbles in the ring (to total around 20 marbles). Players take it in turns to drop marbles from eye level on to the marbles in the ring. Each player keeps any marbles pushed out of the ring. Play continues until all the marbles are claimed.