Does anyone have experience house hacking by hosting foreign exchange students? How much monthly income could that produce? We are empty nesters with a huge 3800 sq. foot house and two bedrooms with on suite bathrooms that are not being used. We like the idea  of hosting international students, rather just renting rooms out, but are wondering how much money if any can be made on it?

A foreign exchange student is typically in high school and hosting them is not a money making venture.  The compensation you receive is a small stipend and the culturally rich experience you receive from living with somebody from a vastly different society.  You and your family would be expected to teach the student about American culture, attend exchange programs hosted by the school to learn about their culture, ensure that the student is adjusting and adapting well and generally being more their "parent" than their "landlord" while they are staying in your home.  This generally works best if you also have a high school student that is their peer, but that is not strictly necessary.

If what you are thinking, however, is hosting an international college student, that would be completely different.  If you speak a foreign language, then hosting foreign college students (not technically an "exchange" student) who also speak that language would be beneficial for them as tenants and you as landlords.  Contact your local university's foreign outreach division to find out how you could be placed in touch with college students from other countries who are seeking housing. 

Usually foreign college students are supported by their wealthy parents, so you will have dependable rent. NO STANDING ON THE TOILETS! Believe it or not, many foreign students will still try to squat on a sit toilet and this can result in damage to the toilet and possibly horrible injuries if the toilet breaks. I know it sounds silly, but I have direct experience with this issue at college.