Mr Hales said the karakul wool from his exotic sheep was particularly good for felting.
"It's actually awesome for felting and I've washed it all myself and then, to make it easier, I had it carded locally by Kane Carding."
For the students, learning the processes which go into turning the wool into warm, cosy slippers was fun. "It's really good, learning this," Sophie Meek said.
Jimi Shotter and Harvey Trent were keen to tap into Mr Hales' experience as they built up their eight-layer slipper sandwich which was soaped and felted.
"When you make your second foot it will be easier. Yeah, right," Mr Hales said. "And remember, there's nothing worse than walking along and finding the bottom of your slipper falling off, so take care."