Form a circle with the preschool students. Introduce the letter "B" sound to the preschoolers. Say "beach ball," emphasizing the sound the letter B makes as you toss the ball to a child. Instruct the child who catches the ball to say "beach ball," and have her toss the ball to another classmate.
Blow up several different-sized beach balls. Have students line the balls up from smallest to largest. Find the balls that match, either by size or color. Count the beach balls with the preschoolers. Add one more or take one away and have them count again. Introduce math concepts, such as size, measurement, comparisons, addition and subtraction.
Stand in a circle in the center of a classroom or gym, that does not have anything breakable nearby. Have all of the preschoolers hold the edge of a sheet, and toss a beach ball in the center. The students need to work together to bounce the ball up and down without letting it fall off of the sheet. See how many times they can make the ball jump. Alternately, pairs of students can hold a beach towel at each corner and toss a small beach ball up and down. Show the children how to work together to toss the beach ball to a different pair of children, without letting go of their towel.
Lay butcher paper on a washable floor, or outside in dry grass. Roll a small beach ball in finger paint and have the kids make beach-ball prints. Press and release the ball to make prints, or roll it down the piece of paper for a different look. Use finger paints to finish the picture.
Set up an obstacle course for preschoolers to test their skills, with a beach ball. Hang Hula-Hoops from the ceiling, or a tree outdoors. Have the kids take turns tossing a beach ball through the hoop. Provide different-sized balls for more of a challenge. Alternately, set up boxes or laundry baskets to throw a beach ball into. Place blocks or empty boxes in a pyramid shape, and have preschoolers roll the ball to knock down the tower.