So if you have a senior and you get your EFC, what happens the next year when your other two go to college. Is your EFC the same if you have three kids in school that it was when you just had one?
each of your kids will get their own FAFSA EFC. The total of all three will be about the same as if you had one kid in college.
BUT that does not mean you will get more need based aid from any college. This is school dependent.
I would very strongly suggest you run the net price calculators on EACH college website for your kids. That will give you a better estimate of your actual net costs at a school than the FAFSA EFC.