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Wintry Science
Tweet Wintry Science Here’s a seasonally related temperature experiment exploring what happens when we freeze oil & water You will need: a clear plastic container, water, cooking oil food colouring (optional), use of a freezer. Instructions 1. Pour some water into the clear plastic container. You can add some blue or green food colouring [...]
Blue Sky – Red Sunset
Tweet Whenever it’s not completely filled with clouds, we can see that the sky is blue. As our world turns the sun rises and sets, and as it sets it looks red. These two observations are related. You will need: A torch a transparent container with flat parallel sides (a 10-litre [2½- gallon] aquarium is [...]
Diving Ketchup!
Tweet There are many variations on this effect – we’ve covered the concept before. However this has to be the simplest to do with the best explanation. Place a ketchup packet in a bottle of water and make it rise and fall at your command, as if by magic. Of course, the magic involves some [...]
Sponge Rock
Tweet This experiment will show you how a piece of chalk can absorb a great deal of water in a short time. You will need: A piece of chalk Cup of water A Spring Balance or Newton Meter (either way it needs to show grams) Instructions 1. Weigh the chalk with the spring balance [...]
Suspended Bottle
Tweet This is another of those experiments that look like magic – but are really science of course. You will need: Coke bottle or any other plastic screw top bottle Uncooked Rice A pencil or chopstick or any other straight rod Instructions 1. Fill the bottle with uncooked rice. 2. Plunge the pencil straight [...]
Experimenting With Naked Eggs or: Naked Eggs Part Two
Tweet If you made naked eggs in Naked Eggs Part One you can now experiment with them in Naked Eggs Part Two! Find out about osmosis – the movement of water across a membrane. You will need: at least 2 naked eggs, containers large enough to hold a single egg and some liquid (coffee mugs [...]
Mutant Marshmallows
Tweet In the microwave, an ordinary marshmallow will puff up until it’s enormous! You Will Need: marshmallows paper plates or paper towels microwave oven toothpicks (if you want) food colouring (if you want)…and adult supervision. Instructions Put two marshmallows on a paper plate or paper towel. Put the plate in the microwave. Set the timer [...]
Rainbow in a Jar
Tweet Another one that could hardly be simpler, but is also very good science and in this particular version makes a display of wonderful colours. You will need: Blue washing up liquid Corn Syrup Blue and Red food colouring Olive Oil Rubbing Alcohol (Isopropyl Alcohol – available from the chemist) Plus… a spoon measuring cup [...]
Racing Lolly Sticks
Tweet How do you make a lolly stick race across water? Would you believe me if I told you all you needed was a drop of washing up liquid? You will need: Water and a large container – we used our water table, but you could even do it in the bath. Washing up liquid [...]
Spooky Lava Lamps
Tweet Lava lamps are easy to make, but really impressive for children to watch. You will need: A clear plastic bottle or jar A bottle of vegetable oil Water Alka Seltzer Food colouring (a spooky colour!) Instructions Fill the bottle or jar a quarter full with water. Top up to the (near) top with the [...]