The day at Wincanton was organised (and paid for) by The Beano themselves, which is the first time they've taken me into schools. I do hope they were impressed, it would be nice to do more.
The celebrities they chose for the "treading on a worm" routine were Declan Donnelly, Miley Cyrus, Nelson Mandela, Benedict Cumberbatch, David Walliams and Katy Perry (with Simon Cowell being suggested but not finally chosen in 4 out of 6 classes).
Kev F Sutherland, as well as writing Bananaman in The Beano, runs Comic Art Masterclasses in schools, libraries and art centres - email for details, and follow him on Facebook and Twitter. He's been writing and drawing comics for 25 years, he must know something.