This can be a very helpful site, so don't give up.
From one who is there (and been there), the best non-legal advice is to NOT count on child support for your child's day to day needs; even though that it what it is intended for. If an ncp does not want to pay, they won't; if they can't pay for legitimate reasons, there is no slush fund for the CS to come from and the burden (responsibility) will fall on the CP. It's just part of the deal of the privilege of being the primary/custodial parent.
The involvement of enforcement agencies offers hope, but it can be false hope. Again, if an ncp does not want to pay, they are not going to pay. They find lots of ways to skirt enforcement actions. If you are not on state aid, your case will possibly (likely) be on the back burner with the enforcement agency...arrest warrants may be issued, licenses suspended...but this does not bring in the child support, but offers hope it will. I would not count on a quick result; CS agencies are underfunded and overwhelmed with cases. It can take months to even get an enforcement order in place. Forgive me, wonderful attorney's on this site, but spending thousands of dollars in legal fees to enforce child support seems to be throwing good money after bad.
As far as the credit card debt your ex is responsible for, you may be able to file a civil claim against them if the debts are clearly outlined in your decree and you can show proof there has been no payment towards this debt.
I, too am an educator. I have been very thankful for the opportunities the schedule allows to work extra jobs or in the summer, to do exactly what you are trying to do. It may take a while, but you can do it...even without the child support. It will be a great thing when and if you get CS, but remember, never, never count on it.