Job advice. Please help!

Okay so here's the deal. I've been at my job for a little over a year now. I enjoy it pretty well. It can drive me nuts but what job doesn't? I've been the sole income for our family while my SO has been taking classes. He completed his classes in August and recently took the state licensing test to become a journeyman electrician. He had an interview today and has been offered a job. It's entry level since he has no work experience in the field yet. He would be making the same salary as I make. The problem is our children. We have 3 young children and one on the way. With both of us working, we wouldn't qualify for daycare assistance and one of our salaries would pretty much go entirely for daycare costs. I have no issue with being a stay at home mom and would actually prefer it, especially since my job wouldn't be protected my FMLA and I may be out of a job come June anyway. We're leaning towards my SO taking it because it seems like a no brainer, but they want him to start Monday which means I wouldn't be able to give proper notice at my job and I would leave them in a really tough spot which I hate to do. What in the world should I do?