Fifteen year olds are at least fifteen years older than ten year olds. That's a big age span. I smile too, seeing how different the song lists are for the U.K. and the U.S. I wouldn't risk my life performing the U.K. songs for the most part, for U.S. kids 10-15. Over here, I find that many kids respond to the beat much more than the story. I got a big kick out of doing old folk songs at a street party one year, and seeing the young black kids get up and start dancing, and doing impromptu buck and wings to the music. They especially liked old country blues and black gospel, as long as it hada back beat.   

Toward the 10 year end of the age span here, I've found that kids love songs with violence. They especially like The Farmer's Curst Wife. One group came back the next year and one of the kids asked me to sing that song about the woman who split open a little devil's head with a hatchet.

Jerry