The boys, divided in two teams, charged up their weapons before we moved into the area of combat - a dimly-lit, grey-carpeted maze. The purpose of the game is to take members of the opposing team by surprise and shoot them by aiming your "gun" at the electronic vest everyone wears.
Pounding music started up, and they were off. I watched in horror. The boys held up their guns so realistically and took such pleasure when they shot others. The intensity of their expressions distorted their faces. I couldn't bear it any longer and went outside and waited, watching the video game players.
There was not a single woman or girl in sight. Young men came and went in groups or singly, but never accompanied by any member of the opposite sex. Our trip had been open to girls and boys. Forty boys had subscribed, no girls.
My group emerged 30 minutes later, the Red team flushed with victory, the Greens indignant in defeat. Each boy was issued with a print-out showing how many of their shots were on target.
I found it profoundly depressing. We look with horror at shootings in American schools, but we are encouraging the same attitudes. My school will not be taking pupils on any similar trips but, given the chance, these boys would be back next week and some may well be after a bit of "real action" in a few years.
* Lynne Field teaches in the West Country