Float your boat
The children took a scientific approach to finding the best design, discussing how the boats might overcome excess weed on the school pond and investigating airboat designs on the internet. They experimented with displacement, investigated the relationship between weight distribution and speed and learned about electrical switches and circuits.
All the children then manufactured a polystyrene hull for their own designs using vacuum-forming technology and installed a motor to operate a fan to propel the boat. Finally, all the boats were put through a trial in a four-metre length of rain water guttering in the DT workshop.
The children were fortunate in being able to use the extensive modern design technology workshops of their associated senior school, Westonbirt, whose campus they share, but high-tech facilities are not essential to the project. This gives it a wide appeal - with the exception of the plastic hull, the airboats can be made entirely in the classroom with hand tools.
Only the vacuum-forming of the hulls requires specialist machinery, and most primary school teachers will probably have no difficulty finding a local secondary school with suitable equipment they can borrow for the half-hour required.
The low cost of the project is another attractive aspect: we calculate that each boat cost around 65p. Many of the components cost next to nothing - the switch, for example, was made from a paperclip and two drawing pins.
The children's enthusiasm for the project was huge, not only during the design and manufacturing process, but long afterwards. The airboats were proudly displayed in the classroom for a long time, with not only parents but grandparents being instructed to make a special trip to the school to view their handiwork. We have the satisfying feeling that a lifetime's interest in design and technology has been encouraged.
John Sproule Head of design and technology at Westonbirt School Tessa Lentel Class 4 teacher at Querns Westonbirt School