The wind moves things invisibly most of the time. Give the students a square of card stock marked with diagonal lines and a center point. Have them cut along the diagonal lines to a point a half-inch from the center of the square. Bring the left corner of each segment to the center and push a thumbtack through the corners and the center point. Poke a thumbtack through the side of a straw near the top of the straw. Have the children blow on the pinwheels and send them spinning. Another option for this activity uses bubble solution and a bubble wand to set the bubbles floating in the wind. Have the students mark the direction of the wind and how quickly the bubbles travel. The wind exerts force to spin the pinwheel and float the bubbles.
Ancient cultures learned the wind could move ships across the water. Place a toy boat in a large pan of water. Blow on the boat with a straw and watch the boat move on the water. Push a small lump of clay in the bottom of the boat. Insert a bamboo skewer mast and sail into the clay. Blow on the sail with the straw, and ask the students which boat configuration moves easier and faster. Show a video clip of a crew operating a sailboat. Have the students watch how the crew uses the sail and rudder to move in the desired direction.
While humans have harnessed the wind for beneficial purposes, nature can use winds destructively. Show the kindergarteners video clips demonstrating the destructive force of tornadoes and hurricanes. Explain how to respond when the sirens warn residents of tornadoes and wind shears. Review safety measures for heavy winds. Point out the safest place in a house during a windstorm. Have kindergarteners practice moving away from windows and under desks or into a safer area of the school, such as a windowless hallway.
Tape cardboard walls to three sides of a cake pan and fill it with sand. Place the pan inside a cardboard box with one side of the box removed. Aim a portable fan at the pan and turn it on low. Have the kindergarteners watch the wind move the sand from the open end of the pan against the cardboard at the opposite side of the pan. Level the sand and add tall rectangles of clay, a large rock and toy trees to the sand to represent buildings, mountains and flora. Turn the fan on again but at a higher speed. Have the students examine how the sand mounds up against the structures. Let them examine the clay and notice how particles of sand embed in the clay. Explain that these can eat away at structures over time.