The shuttle is always okay. I always beat the shuttle kids when I drove myself to the academy but it's no fault to you if you are EVER late if it was due to the shuttle. Can't beat that.
Just be sure to tell the driver that it's your first day and need to stop at the security building. Someone from student services will drive you to your class from there. You'll have plenty of time.
Take the shuttle....it passes through the parking lot for the building youll be going to anyway....and ypu cant be late on the shuttle, cant go wrong there