In my opinion, education for prisoners not serving life terms... PARTICULARLY for those with property offenses... should be mandatory. It's a no brainer. I don't understand why we don't mandate that? We should mandate work AND education for prisoners.
If I had my way... your release would be predicated on the achievement educational goals set for you by a warden.
I immediately tried to think of how the incentives could be set up this way and unfortunately couldn't come up with anything that didn't seem susceptible to gaming.
Ie, offer prisons a tasty carrot -- if it's tasty enough to be attractive, you get the same link between sentencing-happy judges and prisons. Sentence people who don't deserve it for a couple of months, they get out and don't reoffend.
In my ideal world the prisons would offer job training/therapy/etc.. and generally just start treating prisons like people, but it probably would be too easy to game. Prisons would probably try to game transfers to move high-risk to re-offend prisoners to other prisons. Sentencing gaming like you mentioned, probably lots of other odd and interesting unethical hacks that I can't even think of.
Just re-enforces my personal belief that for-profit persons are not a good idea at best, and immoral at worst.
Because prisoners being rehabilitated and rejoining society is contrary to the interests of the prison industry.