I've never heard of this thing, but we had a similar programme where I grew up, where an older kid called "Scouse Jimmy" taught us to make play-explosives out of cap-gun caps, sellotape, 1p coins, matchstick-heads and tennis balls.
I don't think it was officially organised by the school - probably a lack of funding for that sort of thing, so it was more of a voluntary self-led after-school community activity.