None. Or, more importantly, not enough for it to matter. You'll see some philosophy, you'll see some tone, but scheme, in the world of college football, is not something you should expect to see at a spring game.
Scheme is, for the most part, game dependent. It is how you attack the opposition's weak side linebacker or get after their right guard. Scheme is a very specific monster that coaches hold close to the vest and only expose when they think they can deliver a knockout shot.
Spring games are less about scheme and more about sating the masses. If your fanbase thinks you need to establish the run, you spend your spring game establishing the run. If your fans want a high octane, explosive team then you spend your spring game proving that is what you are.
In other words, spring is not about showing scheme and how you plan to attack defenses; spring is about making sure that the masses stay in line and get what they want.
There's a reason Paul Johnson, at Georgia Tech, throws the ball around the yard and has an upbeat spring session. Not because that's the plan for the fall, but because folks need to believe that is what they are going to do. The same goes for LSU and opening up the playbook, pretending that they will be more than a smash mouth team who wants to out muscle opponents.
The spring game is where coaches build goodwill. They show off the highly touted freshmen and let the kid who people think should be a stud, be a stud. It is a lot less about scheme than it is about putting on a clinic. You show people what they want to see, set up a scoring matrix that supports what you need and go from there.
Spring is not about scheme. At least not the spring game. Spring is about proving to Joe Fan that you fixed your issues, that the future is bright and that they should definitely buy season tickets. If you want to see the real issues, you watch 9-on-7 drills during practice 12, where the defensive line is abusing the offensive line and the running back doesn't gain a yard during the period.
That said, new coaches do try and work their beliefs and philosophy into the spring game. Paul Chryst pushed the power mantra at Pitt in 2012. Jim Mora showed that being physical was going to be a part of UCLA football in his first contest. Larry Fedora, at UNC, wanted to prove to folks that tempo and energy was what his teams would be about.
You will see philosophy, but don't expect much scheme out of spring games. What you should expect is to see a focused effort to address the very real issues that every team has.