Look for full time teaching opportunities even ones out of state. Many schools are hurting for teachers and it wouldn’t matter that your degree isn’t education specific.

If Partner A pays the mortgage and Partner B pays the bills that would be fair. Also Partner B should buy the groceries to even things out a bit.

That is too close for comfort in my opinion to live on one income. Future expenses to consider: large unexpected medical bill, therapy expenses, child extracurricular or field trip, savings for kids college and braces, new vehicle expenses when current cars get old, major home repair or renovation. You would be in a better situation to maintain 2 incomes while hiring a housekeeper or part time nanny to help with the kids.