There aren't any protein powders specifically designed or aimed at 14 year olds, but whey protein would be completely safe for 14 year olds, since its basically derived from cheese. Insure it is just whey protein your buying though as some powders may have things in that would be dangerous to 14 year olds (mainly testosterone boosters)
Animated Powders - 1910 was released on: USA: 14 September 1910
At 14 years of age, the best supplements your son could take are eating eggs, meat, and protein powders with whey, but start small and work his way up.
10-14 days
14
14
Ages 10 to 14 Girls Ages 12 to 16 Boys
14-17
The two main characters are ages 13 and 14.
Megumi's Workout - 2013 was released on: USA: 14 February 2013 (Beloit International Film Festival)
For 63, 51, and 14 the LCM is: 2142
PG-13 for 14 and up ages.
They are 14 and 12 I think