If I were you I would take a look at the Darton bows.Three in particular. Depending on their size and strength, the Ranger 3. the AS25 or the AS50. All of them have alot of room for growth and if I remember correctly they come with all the modules to adjust the draw lenght. The 50 is a parallel limb bow but the others aren't. I just bought the Ranger for my 13 year old and it is doing great. It has an adjustable draw length from 17 to 28 inches and draw weight form 15 to 45 pounds. I will probably let him use the Ranger through this year then move him up to the AS50.Good luck with your search an I think you are doing a really good thing getting those youngsters into archery. You all will have a blast together.