Im dreading the day we have to tell my kids that mom is moving out. Its going to destroy our 6 year old.
There is no easy way to do it. I'd fight to wait until summer break, if I were you. School's hard enough for them when things are right, and to do that in the middle of the school year could have negative effects.
There are moments in this life when you are so confident in the rightness of your actions, that not even for a second do you consider the option that you might be wrong.