If you must replace outdoor recess with indoor activities, students can still remain active. In "Red Light, Green Light," stand 15-20 feet in front of the students, and clear out a space in the middle of the room. Have the students walk or run toward you when you say, "green light" and stop when you say, "red light." Children must drop out out if they fail to stop on "red light." The winner is the one who reaches you first.
In "Running Colors," put out mats of different colors and have students run to them when you call out the colors.
Let the children create. Set out a variety of arts and crafts supplies, such as play dough, modeling clay, craft sticks, paper, markers, colored pencils, glue, glitter and sequins. Let the children pick the supplies they want. Tell them you want to put their work in the classroom art gallery to display for other classes.
If you can get away with a noisy classroom for a short time, let the kids pick instruments and form a big band, playing however they feel like playing.
Put on some lively music and have students (individually or in small groups) do their own interpretive dances.
Get in a circle and sing favorite classroom songs. Share a couple of your own favorite songs with your students.
Help the students decorate sugar cookies with colored frosting, sprinkles and M&Ms. Or have them make ants on a log -- the ants are raisins, adhered to peanut butter to a log (a celery stick) -- or apple "smiles" (place marshmallow "teeth" on peanut butter "gums" spread on two apple slices (lips) with red skin.