Explore bitter, salty, sweet and sour tastes by doing some taste testing with your preschoolers. Give each child a plate with a life saver, a cup of unsweetened lemon juice, a potato chip and unsweetened cocoa powder. The kids can taste each item and describe the type of taste. Have the children experiment with what happens when you add sugar to the unsweetened lemon juice. Another option to explore taste is to compare the difference between hot and cold liquids.
Provide children with a variety of textures to experiment with. Mix some rougher materials into a few colors of tempera paint. Try adding coffee grounds, salt, oatmeal or sand to each color. Have the preschoolers experiment with finger painting each textured color. Challenge them to guess what is mixed into each color and describe what it feels like.
Experiment with a variety of reflective surfaces. Begin with showing the kids a mirror and talk about what a reflection is. Pass out other shiny items, such as spoons and tinfoil, to examine what their reflections look like in each item. Have a toaster and bucket of water available also for the preschoolers to check out their reflection in. Give each child a small, unbreakable mirror and have them experiment with what happens when they breathe their warm breath on the mirror.
Practice identifying sounds with and without earplugs or headphones on each child. Their eyes can be closed for this activity. Use items around the classroom to make individual noises, such as crumpled paper, a whistle, running water or loud footsteps. Discuss with the class members how their hearing was affected by wearing earplugs. Expose preschoolers to a variety of musical instruments and singing voices. Discuss the differences and similarities among sounds, as well as musical notes that sound high versus low.
Offer a variety of foods for the kids to smell. This activity can be done with or without blindfolds. Compare cooked vegetables to raw vegetables and discuss how one type has a stronger smell than the other. Dip cotton balls into different scents, such as vanilla extract, perfume, baby powder and garlic powder. Compare the scents and encourage the kids to guess what each scent is.