The children of The Grove county primary school, Cambridge, listening eagerly to the story, shared Alexander's horror. "Ughh!" they shrieked as Aunt Mabel handed each guest a tin and told them to put it to their ear, listen and guess what was inside.
Bob Hartman, a professional storyteller from Pittsburgh in the United States, acted out the five characters round the table through facial expression, voices and body movement. Alexander was shy and apprehensive. Aunt Mabel looked on the bright side. Tom warned that each tin in turn "sounds like dog food".
Characters, Bob explained to the children and teachers he met on his recent UK tour, are one of the main ingredients in a good story. Then there is the setting to consider and the central problem or conflict. And repetition is important, as Bob demonstrates in "Aunt Mabel's Table". This story of a poor woman who had to buy unlabelled tins to feed her family is one of the many true stories Bob tells from his childhood. He publishes several collections a year, which are translated into a dozen languages, and some of his tales appear as picture books, such as Cheer Up Chicken!, published this week.
Bob's love of storytelling began at his elementary school in Pennsylvania when the teacher would settle the class down after lunch on Fridays and spend the whole afternoon reading them stories.
"It was fantastic," he remembers. "Everyone looked forward to Friday afternoons. It was so different to all the other lessons, but those stories would go straight to our hearts. It made a real impact on me."
Bob spent eight years in England as a pastor in a village near Leicester, and started storytelling with his brother when he returned to the United States. His style is energetic, with lots of different voices for the characters, gestures and movement.
"We communicate what is important in our lives through stories," Bob explained after meeting the children from The Grove. "It's part of our way of understanding our experiences. All stories from every culture all over the world have a problem at the centre that has to be solved. It's a way of identifying the challenges we face and coming to terms with them."
The eight to 10-year-olds from The Grove heard a story from Bob's latest book, The Lion Book of World Stories - a tale from Japan about an old man who saves his village from a huge wave. They also made up a story about a lizard and a python called Jack and Derek, who lived downstairs from a rat and a crocodile called Tom and Jerry. And Maria Jackson, 10, said she was writing her own story about a mother who was trying to be like a teenager, called "The Groovy Mum".
Eight-year-old Jamie Bishop said his favourite authors were Roald Dahl and Enid Blyton. He was writing a story about waking up one morning to find he had become an ancient Egyptian. "You can do anything you want in a story. Sometimes they can help you learn about things, like what it must have been like living in ancient Egypt," he said.
Back at "Aunt Mabel's Table", there was a happy ending for Alexander. What he feared might be dog food turned out to be chocolate pudding.
'The Lion Book of World Stories' by Bob Hartman, Lion, pound;9.99; 'Cheer Up Chicken!' by Bob Hartman, Lion, pound;7.99