Have children plan their own classroom circus. Talk about some events that are often done at the circus, such as juggling or lion-taming. Break children up into groups and let them choose their own events. They can practice and perform real circus events or create their own. For instance, children can create tumbling or dance routines. Even if their demonstrations aren't traditional circus activities, children will get practice performing for others. Help children put together costumes from the dress-up bin, then have groups take turns performing for one another.
Walking a tightrope helps preschoolers develop their balance and coordination. Place a long piece of string or piece of colored masking tape down the center of the room. See if children can walk down the line putting one foot directly in front of the other with their arms held out to the side for balance. You can also take children outside and have them pretend a curb is a tightrope. Walk along next to them to catch them if they fall.
Although many people are scared of clowns, children won't be so intimidated by them once they've dressed up in clown gear. Get permission from each child's parents to apply face paint to him, then bring in child-safe face paint. You can paint children's noses red, give them brightly-colored eyebrows and paint the area around their mouths white. If you don't want to paint children's faces, you can have each child decorate a paper plate to look like a clown face. Cut out the eyes and nose, then tie the masks onto children's heads with elastic or yarn.
Let children use their imaginations to create circus-related crafts. Give children paper bags and art supplies to make animal puppets, such as lions or elephants. Children can pretend to have the animals do tricks. They can also create colorful circus tents. Have children cut long strips from colored paper or tear off foot-long strips of crepe paper. Children can glue or tape one end of each strip to the underside of a paper bowl. Poke a hole in the bowl and tie on a yarn handle. When children hold the bowl from the handle, the strips will dangle over the edges of the bowl and look like a striped tent.