My ex husband lives in Costa Rica, and has not honord his promise to pay child support as agreed in our divorce settlement. "child support" being the monthly school fees. I live in South Africa with our 6 six year old son, he lives in Costa Rica.

International child support collection is probably not going to be easy. First thing I would do would be to contact a lawyer in Costa Rica to see what can be done. Costa Rica may possibly have a child support collection agency, I suppose; so check on that too.