Welcome to CS Andi! Tell your wife that there really isn't anything to be intimidated about. Yes, meeting and talking with complete strangers can be a little scary at first, but the great thing is you get to screen who comes into your house and who doesn't. We've only hosted 2 times, and met up with other CSers 1 other time. Take it slow and maybe just host a person for only one night to start out.

As for unschooling, we are unschoolers/eclectic homeschoolers. There are some schools in Germany that do allow for the unschooling like method: check out the CS unschooling group: http://www.couchsurfing.org/group.html?gid=7927

Happy hosting and surfing!