Leah it is always a hard thing to do, I have just got a new job yesterday ( I am a primary school teacher too) and I had to tell my new principal who i have never even met yet, that I am pregnant, and that was really hard. But she was really understanding and said that everything would be fine. So just do what is right for you, and doont let anyone make you feel that you are making the wrong choice for you or your baby!