Teach the difference between hard and soft objects through a hands-on activity. Place six dense, unbreakable items on a table, or lay them on a blanket on the floor. Choose blocks, drinking cups and other solid items. Beside these, place six soft items, like cotton balls, feathers or small stuffed toys. Invite toddlers to touch the items. Pick up each item and name it. Ask youngsters if the item is hard or soft. Demonstrate that, although the cotton ball can be squished in your hand because it is soft, a block is hard and keeps its shape. Encourage children to pick up each item to feel it, then tell whether it is hard or soft.
Plan an activity with toddlers to explore the sense of taste. Place salted pretzels, vanilla wafers and lemon slices on a plate. Name each food before tasting. As you and the children sample a pretzel, mention the food has a salty taste. Point out the salt granules on the pretzel. Taste the cookie and describe the sweet taste. Advise toddlers to nibble the lemon slice, instead of taking a big bite. Discuss the sour taste of lemon. Ask children to describe the way each food tastes and to choose a favorite. Name other foods that taste similar to the items on the plate.
Fill a dish pan or classroom water table with lukewarm water to conduct a science activity with toddlers to determine if items sink or float. Provide three items for the experiment that will sink. Use a die-cast toy car, metal spoon and a stone. Choose three more things that will float on the surface of the water, like a plastic block, bath toys or sponge. Before placing things in the water, ask the children to guess whether the item will sink or float. Let children drop items into the water. Explain in simple terms why each item stayed at the top or sunk to the bottom.
Show toddlers that water transforms from a solid to a liquid. Place an ice cube in a plastic bowl. Put the bowl on a surface that is accessible to toddlers, so the transformation can be monitored. Let the children touch the ice cube. Ask them to describe the ice. Explain that ice is frozen water and when ice is placed in a warm room, it melts. Periodically check the ice cube with the children to observe any changes. When the ice has melted, let the children touch the water in the bowl. Explain that the liquid and the solid are both water, but in different forms.