WHat I usually do is take my old arrows that have dings, nicks, etc.. take them to the bandsaw and cut them down to my sons draw length. generally, the imperfection on a damaged arrow (for instance one that I hit something hard with and shoved the insert up into the shaft) are up toward the front of the arrow. When I cut down the arrow to my boy's draw length it usually removes the damage and the arrow works perfectly for him. Call me a cheapo I guess...
You can also buy field points that are 45, 50 or 60 grains and will fly better out of a light bow than 100 gr.