Can you go to school after obtaining employment based Green Card?

I am not exactly sure what you mean by an employment based green card. If you have a green card, I would imagine you are a permanent resident. If so, you are treated in general as any American citizen and can go to school as you wish. However, if you are in this country on a work visa (for example H-1), then you are here to work, not to go to school. In addition, if you are planning on going to school as a full-time student, you must obtain a student visa (F-1), and that means you can study, but not work (There are some exceptions for part-time work and practical training).