Science: Lending Old Ideas Some Resonance

Modulated Tesla Coil

With Science Week fast approaching excitement is building in anticipation of what Mr Childers has in store. During the first half of the Spring term however, pupils at Bede's Prep School have built a light-sensitive theramin. It's wacky, says the Head of Science, but practical examples are necessary.

"We started with an iPad for inspiration," says Mr Childers, surrounded, as ever, by pieces of custom-built technology. Behind him tanks full of snakes, spiders and rodents rustle with activity.

"The students wanted to know how it worked. The theramin idea came from that."

Using a series of widely available pieces of electronics, the group of students then started to build their machine. The seemingly complex contraption which resulted from their efforts is, however, according to Mr Childers, built from very simple principles.

"There are five key parts to it," he says, "a speaker, a battery, light dependant resistors, a capacitor and a transistor. The most intricate part was building the electromagnet, but they soon discovered that it's not hard to build an electromagnet - it just takes a bit of patience, coiling all that wire."

ThereminThis latest experiment is one of many similar enterprises undertaken by the Science Department at Bede's Prep School. Last term apparently it was a modulated tesla coil.

"The Year 8's helped build that one," Mr Childers continues. "It's rather dangerous frankly. 240 volts open. But we have a safety box and the way we manage it the device poses no risk at all to pupils. Once again though, it's a machine assembled from very simple principles."

The construction of the tesla coil was inspired by the children's study of the flow of current. Building a machine such as the one on Mr Childer's workbench is unusual, he admits, but at the same time he says there is nothing quite like practical science.

"These experiments are a bit wacky, but there is so much contained in them that the kids need to know anyway. And it's something slightly different.  You simply wouldn't get it anywhere else."

The next machine along on the workbench is a Jacob's Ladder which, when Mr Childers turns it on, crackles dramatically with multi-coloured ribbons of electricity.

"I rub the sides of the Jacob's Ladder with mineral salts," says Mr Childers, "which is where the colours come from. Some of this Science is degree-level stuff. It's inherently dangerous, but we complete risk assessments. When I'm not here not only is everything safely locked away but I remove all of the fuses, RCD units are fitted to the lot and so on."

As he continues to move around the laboratory, demonstrating device after device, it is undeniable that Mr Childers passion for Science is irrepressible. He describes the webcam he has set up to track the movements of the animals in their tanks at night, his ambitions for Science Week and much more.

"The goal," says Mr Childers, in conclusion, "is to take Science, which can be mundane and boring, and make it real - both in the classroom or in Science Club after school."

From the line of children who then come to visit the lab during break time, it would appear that the Head of Science has achieved that and quite a lot more.