This month we are going to make something very strange: a substance called hydrophobic sand - literally, sand that doesn’t like water. All you need is some sand (the more colourful the better), some Scotchgard, an oven, a cookie sheet and some aluminum foil. There’s lots of drying time in this one, so it will take up much of an afternoon.   The first thing to do is dry your sand. So cover your cookie sheet with aluminum foil (you won’t want to eat either the sand or the Scotchgard), fill it with sand no more than a centimeter deep, and then put it into the oven at 100°C (212°F) for approximately 30 minutes. Take out the cookie sheet and turn off your oven. But - be careful! The sand will stay hot for quite a while, so take care not to spill or let little hands touch the sand right away.   The next part is easy: spray the sand with Scotchgard, coating evenly, and then leave it to dry for 30 minutes. When it has dried, shake it up and coat it again. Repeat this coating/drying process until you have four coats of Scotchgard on your sand.     Once your sand is ready, try pouring it into water to see what happens. It will behave very strangely! Scotchgard is made of a chemical (perfluorobutanesulfonic acid) that repels water, so when they are mixed they desperately try to minimize contact with one another, like water beading on a plant’s leaves or on a newly-waxed car. Sometimes hydrophobic sand will even form into bubbles under water, and float briefly. Compare this to how regular sand interacts with water – it’s a heck of a contrast!   If tricks with weird science materials interest you, visit Discovery Centre on the weekends and take in a live show – from fireballs made of flour to ice cream made of liquid nitrogen, we have a weird and wonderful way to strike your fancy!   For more great things to discover - visit the Discovery Centre on Barrington Street in Halifax, check out their website or join them on facebook ...