Bob Frost cuts a dashing figure at the front of the class. Today, the secondary maths teacher is donning an all-in-one, bright blue, Nasa spaceman suit and a shock of curly grey hair. The Year 6 pupils at Kent's Barton Junior School look up at him in disbelief. This will be their teacher for the next two hours, courtesy of Dover Grammar School for Boys.
Each Wednesday afternoon, Bob goes out to local primaries - he has visited about 30 since September - to raise the profile of the grammar school and get children interested in maths. What follows, as one boy puts it, is "more magic than maths" and pupils love it.
There's the mobilisation of 35 camels to illustrate how fractions work; a piece of rope, cut in half and tied in a knot, which becomes whole again; learning about algebra through Harry Potter, and counting tricks that can be used to con money off older siblings.
The pi ce de resistance, however, has to be the investigation into formulas, which begins with one frog (a boy) and one princess (a girl) sitting on chairs with an empty seat between them. The class has to predict how many moves it will take for each to "leapfrog" into each other's place (195 if all goes to plan).
The pupils work out a formula for this prediction before the hopping begins in earnest. The youngsters are captivated and the game is carried out in complete silence, followed by cheers as the formula (n2+1)squared - 1, is proved to work.
"Maths doesn't have to be boring," cries Bob victoriously at the end. "If you love TV, iPods or your video games, then you love maths. It's the basis of the civilised world."
Not everyone might put it exactly like that, but the pupils' enjoyment is unmistakable. "We don't have a maths specialist at the school so it's great getting an outsider in who is obviously comfortable playing around with numbers," says Jacky Neale, deputy head and maths co-ordinator at the junior school. "Our boys especially love the competitive element. I've never seen some of them so enthusiastic."
Other schools report similar findings. "Levels of engagement in maths lessons have markedly improved since the roadshow and the children are now eager to explore maths outside the numeracy hour," says Alison Dakin from Harcourt Primary School in Folkestone. "It has enlivened the subject no end."