Why not mesmerise the kids with their very own hand-made lava lamp? All you need is a plastic bottle filled with water and a little bit of vegetable oil. Then add about 10 drops of whichever colour food colouring you fancy. Once the oil and water are separated, drop in half an Alka Seltzer and let the kids enjoy the display right in front of them. If they want the effect to carry on, simply add in more Alka Seltzer.
Fun with Skittles
Skittles, the sweets, are very good at dissolving in water. This means that the kids can have great fun making pretty patterns with their treats. Simply get them to place the Skittles in whatever pattern they fancy around the edge of the plate. Then all you need to do is just pour a little hot water into the middle and watch as the colours of the sweets run into the water, creating a pretty pattern.
Baking soda explosion
Baking soda and vinegar mixed together makes for a fun explosive reaction. Why not make it even better by dyeing the baking soda different colours using food colouring? Set the different coloured baking soda strips out on a tray and have a jar filled with vinegar and a syringe so that your child can experiment by themselves. If your child really loves to do scientific experiments, why not visit https://starwalkkids.com/ and take a look at their recommended science kits.
Make invisible ink
You could make invisible messages and teach the kids about oxidisation at the same time with this experiment. All you need is lemon juice. Simply place the juice in a bowl and with a cotton swab write a message on a plain piece of paper in the juice. When it dries, the message will completely disappear. To bring it back to life simply place your hairdryer over the paper on a low setting and watch it reappear. This is oxidisation happening right in front of your eyes.
Make a gumdrop structure
All you need for this experiment is some gumdrops and toothpicks. Get the kids to design structures by sticking the toothpicks into the gumdrops, you could, for instance, challenge them to design a structure that is strong enough to hold a book. You never know, you might be able to explain the fundamentals of structural design while they play.
Kids love making and playing with slime. Why not make it with your children and teach them about polymers at the same time? Polymers are substances that are solids when the molecules are close together but when they are pulled apart become liquids. Mix glue and water with the special ingredient borax, which adds as a binder in this experiment, to turn the liquid into a solid. You can also add food colouring if you want to create different coloured slimes. Once made, you can keep your slime for ages, so long as you store it in an airtight container.