The game, with handmade illustrations has just grossed $30,000 (Pounds 18,750). It inventors plan to build on the success by marketing video and clothing spin-offs to raise $1.3m a year in sales for school funds.

The school in Hyannis, near the famous Kennedy compound on Cape Cod, has been growing short of money even for such necessities as paper and pencils because the many retired people attracted to this picturesque community oppose increasing education spending.

“The tax base is such that schools have to find ways to take care of their own needs,” said principal, Tom McDonald. “If you want to raise money for field trips, you hold a cake sale. Our ultimate goal is to fund our own school. ”

It is unlikely that the young entrepreneurs will actually earn enough to pay for their own education But their teachers say they are certainly learning something.

The students had to make up 560 maths, science, civics and history questions for their board game. They have also learned something about the demands of business, even sacrificing playtime for sales meetings.

The Main Street Learning Game has already nearly sold out its first run of 1,000 copies. Now the youngsters are hard at work on their next project, a colouring book for which they already have 3,000 advance orders. And they are planning a line of T-shirts and neckties and a how-to-read videotape to go into distribution across the US.