Can the school find out where I work after I graduate from college?

No, unless you need any materials, such as party member relations, and need to go back to school to provide materials, the school will know where you are now, or your former teacher knows where you work and has your mobile phone number, otherwise you won't pay attention to where you work. A school graduates so many students every year. How did the school know that they worked there? Nobody cares about these things for other reasons, right? Why do you ask?