Have you ever gotten into a situation where you had multiple adolescents w/ low cub training? Hear me out on this one, its pretty annoying to be in that situation.
All users start out with 2 slots for adolescents on hunting trips. If you could buy 1 or 2 more slots then cub training would be easier especially if you have a ton of adolescents. I feel as if allowing 5 adolescents on hunts would be a little too much so the max number of slots would be 4 (including the 2 slots you already start out with.)
Kind of like male slots, you would need to buy these slots with GB, the 1st and 2nd free, the 3rd costing 1 GB, and the 4th costing 2 GB.
As said before, you can't have more than 4 slots for this or unlimited slots, otherwise the feature would become too over powered.

just a little idea I had while discussing cub training w/ some frenos of mine