E.B.
Mamazita said it well. This is your reality. You had three children with a man who is married to someone else.
Previously you were only receiving child support for two of his three children. Did you get that resolved?
You continue to defend the father of your children, saying he's a great father. What does that mean? Does he pay adequate child support for all three kids? How does he help you in practical ways?
A great father makes sure that his children are secure and loved. A great father is there to feed the babies, bathe them, and read to them. If the father of your children is simply depositing a check in your bank account, then he's not a great father. He's a father, yes. But not a daddy. And not anything "great".
Your kids' father has another family, and it's quite obvious where his priorities lie. You're alone, trying to take care of his children, having to work full time.
I'm sorry that you continued to have babies with this selfish man, but for now, that's the reality. I think you should discontinue the classes. Try to provide a stable home for your children.