I saw a nice project for a garden theme:
give each child an egg carton and ask them to create a "garden scene" on the inside of the cover. Paint, markers, or collage- whatever.
Then put potting soil in each of the "cups" and plant a small seed. Send these home with the children by putting a rubber bamd around the carton. Remind kids to water their seed and wait for it to grow.
Jan Snell