You're obligated to work for First Student for 6 months if they help you get your CDL. If you try to leave, they will cancel your CDL. What this amounts to is a commitment from the driver to work a split shift during the week without considering other opportunities for full time employment. You'll earn part time pay for a minimum of six months with First Student.
Money: $15/hr to start, regardless of experience, with 20-25 hours per week. The split schedule doesn't allow for another well paying full time job. There is no flexibility. Not many am only or pm only routes available to allow you to commit to another company. You get paid every 2 weeks, and direct deposit takes two months to go into effect.
Training can take 4-6 weeks, or longer, depending on availability of the trainers and how well things are coordinated. Training pay goes on your 1st check, which can be 2-3 weeks after your first shift as a driver. Plan ahead and go into this job with plenty of money saved and the bills paid.
Advancement opportunities for salaried positions seem to be very limited, and they will hire from outside before promoting a driver.