Scam. Your wise for asking, don't fall for it.
If you want to grow taller, their are som exercises you can do, stretching ect. Many books on the subject, also check out a forum, called grow taller.
Other than that, supplement with a good multivitamin/mineral, that are in a bioavalable form, and omega 3 Carlson's brand, or Nordic Naturals. Do aerobic exercise, do not lift weights/weight training. Do Yoga.
Supplement with DIM, Di-indole-methane, this has anti-oestrogen effect, some say it can prolong the time you have to grow.
Hope this helps,