Residence permits are issued to people that want to stay beyond their allowed visa stay period for the purpose of touring the beautiful places Turkey has to offer.
All the rules that apply to a visit visa applies to your residence permit - including no employment.
You should never work anywhere without a work permit, no matter the offered wages.
If you’re caught working anywhere without a work permit, you’ll be arrested and deported with an entry ban. The ban could vary from 3 months up to 5 years. It’ll be at the discretion of the duty officer at your departure gate.
Just because you have a work permit to work at a school does not mean you can work at another school or a language center in the evenings or on the weekends.
Work permits are company/school specific. It is issued to you to ONLY work at the school that applied for your work permit. If you want to change your school, you need to get your work permit transferred to your new school. Usually, the HR will take on the task of doing this for you.
The law is very clear that you should have your work permit in hand and ready for inspection by a ministry inspector before you start working at a school. Even if your work permit is in the process of being approved, you cannot legally work. When your work permit is approved in the system, a SMS notification will be sent to your phone by the Ministry of Labor. Normally, the permit will be at your home/school address within 3 days after the confirmation SMS.