Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

Passage: Ergänzungsschulen are secondary or post-secondary (non-tertiary) schools, which are run by private individuals, private organizations or rarely, religious groups and offer a type of education which is not available at public schools. Most of these schools are vocational schools. However, these vocational schools are not part of the German dual education system. Ergänzungsschulen have the freedom to operate outside of government regulation and are funded in whole by charging their students tuition fees. Question: How are ergänzungsschulen funded?
tuition