How can you pass a drug screen while your pregnant?

Avoiding the consumption of drugs is always the best policy but if you MUST get high do so immediately after your doctor's visit giving you the most amount of time to detox naturally before you are asked to pee in a cup again. Drink LOTS of water. Keep in mind that a positive result could lead to you having your baby taken from you.
To pass school while you are pregnant, go and talk to your school's guidance councilor and speak with him/her about your condition. They may be able to offer you classes on balancing your baby with your schoolwork. Just do as you regularly would in school. Study, listen in class, and come organized. Best of luck to you and your baby, and God bless.