Fortunately for the next generation of scientists, Welshman Ceri Evans decided to throw away the trainee teachers' rule book and devised his own style.
He hasn't looked back and is the 2006 Guardian teacher of the year in a secondary school. "When I first started teaching it was hell, absolute hell," laughs the 35-year-old science teacher from Tonypandy. "I just barely passed my PGCE. I was told that if my progress didn't improve I would be removed from the course.
"I would watch my teacher-training mentors and try and copy them, but it didn't work. It was so mechanistic. I didn't believe in what I was doing or saying. I ignored everything they told me to do and did what I felt was right. It's not something I would normally recommend to students!"
He found his niche at Gable Hall school in Essex where the head has "given me the space and freedom to try new things". Among them is a feedback device that he invented. Pupils can choose between smiley or glum faces on a keypad to show what they think of his lessons. "At the end of the day, the kids are my customers," he says. "In any other environment you would ask how am I doing, what can I do better?"
His lessons, including trips to West Ham Football Club and building solar-powered cars, yield lots of smiley faces. Pupils can also track their progress online and email him for homework help on a Sunday night. In the past three years, GCSE A*-C grades in science have rocketed from 29 to 76 per cent; and the 2005 top set took dual science exams a year early.
He also pioneered GNVQ science in the school for those who were better with their hands than exams, resulting in 49 out of 52 passes. "The results have gone up thanks to a team effort and a change in the curriculum that recognises that one size doesn't fit all," Mr Evans says modestly.
His own education took him to Bangor university to study biological science, then an MSc in bio-technology at Cranfield, before his PGCE at Swansea at age 26.
"I went to England because of the shortage of teachers. I was only offered one temporary supply post in Wales, but I would like to come back one day,"
But he shudders at the idea of becoming a head. "No thanks. It would take me out of the classroom."
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