Youngsters turn primary colors into secondary colors when they blend finger paint blobs in a plastic zipper bag. Buy blue, red and yellow finger paint (available in squeeze bottles where children's art supplies are sold). Get three bags ready for each child who will participate in the science activity. Squirt one tablespoonful of two paint colors into each bag. Prepare the first bag with a blob of blue paint on one side and a blob of red paint on the other. Zip the bag closed. Make the next bag in the same manner using blue and yellow blobs of paint. Finish the baggie preparation with yellow and red paint blobs. Double check the zippers to be sure each is closed. Pass three bags to each child. Instruct them not to touch the bags yet. Ask the children to guess what will happen when they use their fingers to mix the squishy paint through the plastic bag. Give them the go-ahead to squish the colors in the first bag. Discuss the results. Ask if they predicted the outcome correctly. Complete the activity, guessing, and then mixing the paint in the remaining bags, then checking the outcome.
Recycle a single-serving size water bottle with the lid to make a science bottle that teaches a kinder-science lesson in liquid separation. Remove the labels and discard them. Take off and set aside the lids, then fill the empty bottles halfway with water. Add two drops of green food coloring to the water, replace the lids (making sure they are tight) and shake the bottles. Point out that the food coloring and the water mixed and ask the children if they appear to be separating. Remove the lids and pour 1/4 cup of cooking oil into each child's bottle. While pouring, point out that the oil will form into bubbles that sink to the bottom and bounce back up to settle, floating on top of the water. Replace and tighten the lids. The children will learn that some liquids are more dense than others and that because oil is less dense than the water, it rises to the top.
A simple, visually powerful kinder science activity is to cover a patch of grass for a period of time, then uncover it and observe the effect. Find a sunny, grassy area to conduct the experiment. Place the lid of a cooking pot on top of the grass. Leave it there for two to four days. Lift the lid and observe the browning and withering of the grass due to its deprivation of sunlight. Youngsters will learn that plants need sunlight to grow.