I thought Show Me Love was a good recommendation, simply because it's a film about teenagers. Some parents might object to its sexual content, though. Y Tu Mama Tambien is perfect, too, but you've got the same problem of sexual themes. My advice is to find a good Coming of Age film, Childhood drama or Teen film, unfortunately most foreign directors use these genres to explore more complicated aspects of adolescent, especially sexuality, so you get films like Louis Malle's Murmur of the Heart. My Life as a Dog is an excellent choice, however. The other route to take is something with an MTV appeal, like Run Lola Run, Ringu or Crouching Tiger, Hidden Dragon. Amelie is a fantastic film, but the hardest thing about this is picking a film that will appeal to both boys and girls. The boys would really go for something like Beat Kitano, the girls however might not.