The baikal viktoria forum has a cute entry on how to make ladybugs out of smooth round stones using just red, black and white paint.
Good for ages 6 and up.
Get the instructions here:
http://baikal-viktoria.ucoz.ru/forum/51-704-3#59835
Get the instructions here:
http://www.oopseydaisyblog.com/2010/04/garden-rocks-for-grandma.html
A moms take makes a whole family using different size stones.
Get the instructions here:
http://www.amomstake.com/2013/07/ladybug-rocks-for-your-garden/
Fireflies and mudpies adds black pipe cleaner antennae and googly eyes.
Get the instructions here:
http://www.firefliesandmudpies.com/2015/05/17/ladybug-stones-a-happy-nature-craft-for-kids/