Try & Fail
Business School really IS a safe space to fail!
Yes, I too rolled my eyes at the notion that the 2 years of an MBA program are the time to try everything 'you've been afraid to try' and so on. In the back of my head I kept telling myself, no way folks, this is the two years when I figure out how to break into that hard to break into industry through blood sweat and tears and am on the path to success.
Well you can do both. In fact you should do both.
There is probably no other time when you will be able to try and experiment with ideas, take as many risks and devote as much energy as you can during an MBA program (except maybe a few years after graduation when you've finally paid down your loans, realized you hate the corporate track and have enough saved up to veer off track).
Run for a leadership position that you never would.
Start a business- for real! Buy a domain and market a thing or a service or a skill you have
Go to that place you never thought was a possibility (use your credit card points to travel)
Apply for a role/internship beyond your current skill set to see what path it leads you to
Add new connections on LinkedIn who you don't think would respond (always include a note)
Try and Fail and if you actually do, dust yourself off and remember there is a pretty good safety net of alumni and administrators who will keep you on the right path.