12 yr old Female and 18 yr old Male Chineese Exchange Student?

I used to teach classes to Japanese junior high school students to prepare them for homestays in Australia. Talking to them after the trip, they sometimes felt overwhelmed by the differences and homesick in the beginning.

Encourage them in the beginning to ask questions and if they're uncomfortable or unsure about anything to speak up. Don't plan out every single day with them, give them a chance to relax or have time to themselves. Also, when you're sitting around the living room relaxing they might be on their toes.... at least at first.

Anything unusual or unique in your area might be interesting to them. Minneapolis probably has a tourism web page with lists of attractions. 12 and 18 are kind of far apart age-wise, but you'll still find plenty for them to do. Of course you can ask them what they'd like to do when they arrive, too.

Hopefully your family has kid(s) around their age for them to hang out with and be corrupted by!

maybe take them to the mall or something of the sort. and actually maybe just a walk downtown would be fun. i know if were visiting somewhere new just walking around seeing how the life it that town goes would be fun