Use the water table to teach children about the concept of absorption. Give children dry sponges to dip into the water. Ask them to explain what happens to the sponges when they're wet, then explain that the sponges have absorbed water. Present children with a box filled with objects they can place in the water. Some should absorb water, such as cotton balls and paper towels, and some should not, such as foil and plastic toys. Let children experiment with every item and find the ones that will absorb water.
Fill the sensory table with sand and let children pretend they're archaeologists. Imprint disks of clay with plastic dinosaurs to make pretend fossils. Let the clay harden and hide them in the sand for children to uncover. To help children build sorting skills, hide plastic dinosaur figurines deep in the sand and challenge children to uncover all of them. Once they've found the dinosaurs, children can sort them into groups of herbivores, carnivores and omnivores. Provide dinosaur books so children can research what dinosaurs they've found.
Sand can be wet or dry, creating two different sensory experiences for children to enjoy. Fill the sensory table with dry sand and let children experiment with scooping up cupfuls of the sand. Move several buckets of the sand into a second table or a large plastic box and add water until the sand is damp. Give each child two identical cups or containers. Help each child fill one cup with dry sand and one with wet and ask children to compare the weights of their two cups.
Use the water table to help children make and test predictions. Present children with a dozen or so water-safe objects found in your home or classroom, such as paper cups, plastic toys and capped markers. Hold up each object one at a time and ask children to predict what will happen when it's placed in the water, then drop it into the water table. Once children have found all the items that float, ask them to study these objects to discover what they have in common.