Painting is an ideal art project for preschoolers because it allows them to be creative. A wonderful way to have preschoolers work together on one of the first days of class is to have them paint a mural. You will need a very large piece of paper that you can lay on the floor or over a series of tables so that the entire class can stand around it. The fun part of this art activity is that the children can choose from an array of applicators including paint brushes, feather, swabs and their fingers. The children will also need access to brightly colored paints. You should encourage conversation about the summer because the children are using bright paints and their summer is likely winding down. This will get them conversing with you and their fellow classmates as they collaborate on a brightly-colored mural you can display for the duration of the school year.
Hosting a short play with paper bag characters created by preschoolers is a good way to encourage teamwork and excite the children by using their creations in a short puppet skit. You will need twice as many small brown paper bags as there are teachers and teacher's assistants in the classroom. The children will work together to decorate different faces you drew previously on white paper plates. Lay out different color yarns the students can use for hair and other miscellaneous accessories the children can add to the plates to create different characters. When the plates are decorated you can glue or staple them to the paper bags and create a puppet skit with the other adult leaders in the room.
Most school seasons begin near the beginning of the fall season, so incorporating a pumpkin into an art project is a fun way to replace a Mr. Potato Head. Have the children sit in a group in front of you and a large pumpkin with a series of holes poked into it. You can have each child come up one at a time and choose a piece for the pumpkin head from a bucket they cannot see into. When they select a piece and look at it, they can choose to put it where ever they want. Having each child take a turn will result in a silly, laughter-igniting pumpkin.