
Quoting
badzombie
Unless it's a rental activity, supported by the payment of actual rent, then the exchange student income is probably line 21 income ("other"). For actual businesses, each business you have should have its own schedule c. Teaching and writing are different activities, though if you report all the income and the legitimate expenses on one schedule c the IRS probably wouldn't kick. That's not how the publications say to do it, though. It is better to group activities the right way so they can follow what you did if they were to audit you.