Many units are divided into preparation and contract system. Whether you are prepared or not is the same, so don't do it, especially don't do bad things. The contract system is hired to work, and the benefits you mentioned will not be given. The unit can terminate the contract at any time and change people at any time. There is no need to give it. It would be even worse if someone left.
The contract treatment depends on the employment of your teacher. There is no special standard, generally between 3000 and 6000, with five insurances and one gold. There may be a gap compared with the outside, but the conditions in the school are very good, and eating saves money, teachers and classmates.