Here are some ideas for bringing your art class outdoors.
Found object collage
Use leaves, petals, stones, or shells to create hair dos. Get the kids to draw the faces and you get two lessons ;)
Pictures with natural objects
Use whatever you find to create pictures of animals, people, whatever you can think of!
Keith Harring style stick people
Use a stick to form part of the body of your stick person. Finish the body with a black marker. Paint around the stick person in a bright colour.
Use a stick to hang strings of beads or shells. Decorate with paint, ribbons or wool.
This is a lovely idea for those with a school garden. Set up a weaving station where children can weave leaves, reeds, and flowers. Beautiful :)
I hope some of these inspire you to bring your class outside for your next art lesson.