WV Hunter, does your son already have a plan for his experiment? If not, here's what I would recommend.

Compare the weight retention and expanded diameter of non-bonded and bonded bullets.

He could use non bonded XTPs and bonded Deep Curls in two different weights (250 grain & 300 grain) shot with the same sabot into the same media with several different powder charges (and with velocities recoded if you have a chrono).

With three shots of each bullet at 70, 80, 90 and 100 grains of powder into damp sand at 25 yards he would have 48 data points to display (80 data points with five shots), and the comparative results of two bullet weights and types of construction would be informative.

If he wants to keep it simpler, he could decrease the number of bullets compared to just two, either 250 grainers or 300 grainers, or decrease the number of powder charges. If he wants it more expansive, he could increase the number of shots to five or ten, or add additional powder charges.

Another advantage is you could buy a box of each bullet and a supply of Harvester short black sabots and have lots of bullets left over to play with yourself.