This is a little complicated but worth the effort. You need a clear jar, water, salt, a couple of live adult brine shrimp (check the pet store), and a goldfish. Ask children which they think is heavier — salt or fresh water. Make a salt water solution and dye it with food coloring. Fill the jar half full of salt solution. Next, VERY SLOWLY fill the remainder of the jar with tap water. This can be dyed a different color from the salt water. The children will be able to see that the salt water is heavier — it stays in the bottom half of the jar. Gently release the brine shrimp and goldfish into the jar. The shrimp will quickly find the salt water area, while the fish stays in the freshwater “zone”. This helps children understand that aquatic animals are adapted for fresh or salt water. Note: Use only goldfish and brine shrimp for this experiment; they are hardy enough not to be harmed by salt/freshwater.
For a wonderful outside (or use the halls of your center) lesson in measurement, buy a 100 ft. rope or twine. Tell the children that the ball of twine that you have is the same size as the largest mammal in the ocean–The Blue Whale. Take the children to a place that will stretch 100 ft, and have them pull the twine until they reach the end. They will be squealing at seeing how large a 100 ft. Blue Whale is. Expand with predictions: How many children would it take to make a blue whale? How many blocks? How many paper plates? Could a Blue Whale fit in your car? Your house? etc..
Oil and Water
Need: cooking oil (Wesson oil), water, water table or small bucket, plastic ocean animals.
Tell the children about the oil tankers that cross the ocean. For whatever reason there is a leak – the oil leaks into the water. But the oil does not mix with water – and it is very dangerous to the sea animals. It covers the animals so they can’t breathe and will eventually die.
Put the oil into the tub of water – then add the plastic animals. Each child should get an animal – ask them to clean the animal. Supply cotton, Kleenex, paper towels – the children will understand how difficult it is to clean oil off.
To create a more interesting water play table, put various plastic fish and underwater animals in the water. Put in rocks, small boats for fishing, shells, objects that might be used for tunnels for the fish. You can also put a little sand at the bottom to give the feeling of the bottom of the ocean. Oh and of course some small plastic plants. Create and ocean and talk about the ocean and the various life connected to the ocean as well as the importance of the ocean to us humans.
Materials: (for each child) a coat hanger, fish pattern, fishing line, scissors, crayons/markers, tape, two small magnets
Bend a coat hanger so that it makes a diamond shape, then bend the hook down so that it is inside the diamond. (It is probably a good idea to do this before hand because it’s a little difficult.) Give each student a copy of a fish shape to color. After it is colored, tape a small magnet to the bottom of the fish. Also, tape another small magnet to the bottom of the hangar. Hang the fish from the hook inside the hanger with a piece of fishing line. The fish should hang just above the other magnet. The action between the two magnets makes them twist and turn as if they are swimming.