Science, along with unfortunate haircuts and unrequited crushes, is something most of us would rather forget about when leaving school for the last time. The simpler the technology we use, the happier we are. We don't want to know what's behind our DVD players, or how wireless laptops or iPods function - we just want them to work, preferably before their warranties run out.
The Dr Bunhead demonstrations are often loud, very messy, and not a little dangerous. But here are 10 straightforward, safe and exciting experiments for the budding junior boffin - or anyone keen to show off in front of friends - to try.
Of course, these experiments, especially those involving electric toasters and expanding soft drinks, should only be done with care and under adult supervision. Use your common sense and enjoy yourself.
Walking on water or parting the seas might be a little beyond the amateur scientist, but you should be able to move water around without even touching it.
Start by running a tap slowly in your bathroom or kitchen sink. Run a comb through your hair several times, then slowly bring the teeth of the comb near the stream running from the tap. When it is about an inch or so from the water, the stream will bend toward the comb.
This remarkable effect is produced by static electricity. The charge develops when electrons jump from one object to another (hair to comb), causing the comb to become charged and thus able to attract water molecules. The experiment also explains why hairs sometimes stand on end when rubbed with a towel, but doesn't help bad hair days.
Anyone who has thrown children's parties is familiar with bursting balloons but, believe it or not, it is possible to stick a needle through a balloon without popping it. First, dip the end of a skewer or knitting needle in Vaseline or petroleum jelly. Then, carefully pierce the surface at the end opposite the knot with a twisting motion and slide it through until it emerges from the other end.
Why doesn't the balloon burst? The rubber at the ends of the balloon is less stretched, allowing the needle to break some polymer cross-links while leaving enough to hold the rubber together. Another neat trick is to place a small piece of adhesive tape on the side of the balloon and stick a pin through the tape.
It should remain intact because the tape stops the rubber stretching to breaking point.
It doesn't resolve the age-old conundrum regarding chickens and eggs and first causes, but this experiment does reveal the egg in a startling new light. All that's required is a raw egg, vinegar and a fair bit of patience.
If you place the egg in a tall glass of vinegar and leave it for 24 hours, you should notice the shell beginning to disintegrate. By replacing the vinegar a few times, the outside shell should disappear completely, leaving a delicate membrane and translucent-looking egg. If you shake it gently, you can see the yolk running around in the egg white.
It's probably best left uneaten, unless you like your eggs raw and seriously pickled.
An experiment that the sweet-toothed should take pleasure in. The phenomenon of triboluminescence can be created by crunching on hard boiled sweets.
If you turn off the lights and look in the mirror while biting hard, the charge produced in separating the sweetie fragments produces a tiny lightning bolt in the mouth. Sugar cubes work best, and crushing them with a pair of pliers might save you a visit to the dentist.
A strange gloop can be formed by mixing cornstarch and water; a drop or two of food colouring can add to the fun.
If it's too powdery, add more water; if too wet, add more cornstarch. The result should be something that can't quite make up its mind whether it's a liquid or a solid. The ooze's identity crisis - technically, it's a non-Newtonian fluid - causes it to act in strange ways.
The more force you apply, the thicker it becomes. This is why those unfortunate to find themselves sinking in quicksand, another non-Newtonian fluid, should try moving out very, very slowly. If you struggle too vigorously, the quicksand will resist.
A light object, such as a ping pong ball, can be balanced in the air indefinitely using a blast from a hair dryer placed below it. According to Bernoulli's principle, the pressure of the fast-moving air stream is less than the pressure of the surrounding air. Even if the ball strays slightly from the stream, the surrounding higher pressure tends to push it back.
Maltesers are optional.
Put a dirty copper coin in a fizzy drink, white-wine vinegar or lemon juice, and after 10 minutes you'll have a shiny new penny. Acetic or citric acid dissolves the copper oxide that has gathered on the surface from exposure to oxygen in the air.
The same experiment can dissolve an old tooth, or a new one, but it wouldn't be wise to pull them out - even for the noble cause of science.
First demonstrated on the David Letterman show and popularised by a series of YouTube videos, the diet fizzy drink/Mentos experiment can get a little messy, so all variations should probably be confined to the garden.
If you place a mento (Polo mints work almost as well) into a bottle of diet coke, the liquid shoots up into the air.
One theory explains the reaction through the creation of excess carbon dioxide, another that the type of gum in particular mints reduces surface tension and creates more bubbles. The experiment has proved so now uses it for a regular lesson on chemical reactions.
Your toaster can be used for something more adventurous than burning bread - try turning it into a machine for flying a hot-air balloon (although do be very careful and don't let children try this unattended).
Roll a piece of cardboard into a tube big enough to fit around the toaster, then place a small bin-liner over the tube. Place them over the toaster and turn it on. The bin liner should rise gently into the air.
Air expands when hot, which means that some air falls out the bottom of the bag. There is now less air inside the bag than out, and so, the bin-liner is less dense than the air around it, causing it to float upwards.
An excellent way to create a very cold drink extremely quickly.
Take an unopened fizzy-drink bottle and cool it for a while in a bath of crushed ice and salt, to a temperature of around -18C. Then, open the bottle carefully and let the fizz out. In under 10 seconds the liquid will completely freeze.
How so? Salt lowers the freezing point of water and prevents ice forming (this is why salt is added to the roads). Carbon dioxide does the same, so when the drink is taken from the salt and the gas escapes from the bottle, the freezing point of the liquid is suddenly higher than its current temperature, hence, instantaneous ice-formation.
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