Working evenings and weekends with some consistency will destroy your social life. If you're lucky, you'll be at a center with Fridays off, but you'll still have to be up early on Saturday. Your friends will stop asking. Seriously.
Time off taken during regular business hours is highly discouraged. If you haven't made yourself absolutely essential, be prepared to lose your hours to other teachers.
There's little regard for your time; If your students cancel at the last minute, C2 will not pay you. If you ask them to pay, often times you'll see a tantrum because you've breached some cultural more... You can choose not to stand down at this point, but be prepared to face retaliation in terms of hour losses.
As you may have inferred, directors at this company have a loose idea of what US labor laws involve. They want you to sign a waiver stating that you waive your right to lunch/breaks during a 6-8 hour day. You may very well be in hostile work environment, especially if you're black, and will have a difficult time threatening to leave because...
C2's NON-COMPETE CONTRACTS are like a scorched earth policy: Unless you work in California where it is NOT enforceable (they make you sign the damned thing anyway), the C2 non-compete contracts make you promise that you will not work in test preparation for 2 YEARS within 50 miles of a C2 Education. As these companies tend to be McDonald's-ubiquitous, you could be in a heap of trouble.
YOU WILL NOT GET AN ANNUAL RAISE WITHOUT A FIGHT... And even then, you may still not get one.
They tell you that to hook you. It's a lie, and it doesn't matter which director you ask in these United States, they say almost the same thing verbatim: there are performance reviews. You can get annual raises.
If you somehow work them above $25 an hour, congratulations. You're amazing. Also, the center director resents you now. Just don't be surprised when the latest 22 year old Harvard grad comes and grabs all your hours at $20 per hour because 1) They have no friggin' clue and 2) the director loves her bragging rights, and 3) You've priced yourself out of your tiny market (Unless you're saved by parents who can tell that someone who majored in the Nietzschean Philosophy is not always well-equipped to interface with a teenaged girl who needs help with Algebra I) . Solves the time off problem, though.
So, negotiate the money you want up front. Be sure to apply to multiple agencies. If you're worthwhile, a competing offer will not be hard to come by.
There are no full time positions for instructors. There are no benefits offered. Even the benefits that the directors get are kind of terrible.
There is no opportunity for advancement unless you speak Chinese or Korean; even if you can speak these well, you won't want to be center director. It's a cruel job, that either attracts abusive people or makes basically good people become abusive.
