Six-year-old Christopher O’Connor watches spellbound as Stewart Death’s head disappears inside the enormous bell of a tuba and he re-emerges with a newspaper. “It was so funny when he put his head inside the tuba to find out why it wouldn’t play,” he says.

A pupil at Abbey Hey Infants School in Manchester, Christopher is taking part in a workshop at this inner-city school given by Travelling by Tuba, two young musicians who aim to “present an entertaining and informative insight into the world of brass instruments”.

When I talk to some of the children after the workshop, they are brimming over with enthusiasm and it is clear that they have learned a great deal about the instrument and its music. Seven-year-old Imogen Barry says she found out “how the tuba’s played and how long its pipe is” and six-year-old Georgie Lidlaw “learned how to play music and what a march is”.

Georgie is just one of the many children picked from the 100-strong audience whom the duo - Gavin Woods and Stewart Death - cleverly integrate into their presentation. She is chosen to play the “hose-ophone”, a length of garden hose, with brass mouthpiece inserted at one end and plastic funnel at the other, which is used by Gavin Woods to demonstrate the mechanics and length of the tuba.

Often the duo bring the entire audience into the proceedings, skilfully persuading the children to clap in time to a march by the 16th-century German composer Susato - played on cornett and sackbut (a medieval form of trombone) - and to join in with the “tick-tocks” between verses of “My Grandfather’s Clock” played on the tuba.

Eileen Walker, a Year 2 teacher at Abbey Hey Infants, is impressed. “It kept the children’s interest for a whole hour and they really enjoyed it,” she says. “Listening is an important part of the curriculum, and it is excellent that the children had the opportunity to hear and touch instruments they’ve probably never seen before.

“We thought there might be too many children for them to manage,” she says, “but their methods of dealing with a hall full of children are excellent and their control is good.”

Last year Travelling by Tuba played at 200 venues throughout the country. And they recently won an award from the National Lottery, with partnership funding from accountants Lloyd and Piggot, for their educational programme in Manchester. This has enabled the duo to give workshops in over 30 schools in the city at a fifth of their normal fee.

John Platt, headteacher at the adjoining Abbey Hey Junior School, recommended the group to the infants school after Travelling by Tuba put on a successful workshop for his seven to 11-year-olds. “We jumped at the chance of having the workshop because it was at such a good price,” he says. “And it was a quality show - Travelling by Tuba are experts who get their enjoyment of music across to kids.”

The duo’s workshop at another school, Haveley Hey Junior, so impressed its music co-ordinator Jon Fisher that he’s organising a return visit. “The school’s in a socially deprived area, so this sort of thing was totally new to the kids,” he says. “But they lapped it up. Getting Travelling by Tuba back will be money well spent - even at their normal fee. And the staff are so keen, they’ve all come up with ideas about getting funding to do it.”

Travelling by Tuba school workshops cost Pounds 170, tel: 0973 763 540. Recitals: Samnewson Centre, Boston, March 5, 7.30pm; Rickmansworth Music Club, March 11, 7.30pm; Melrose Music Society, March 14, 7.30pm