Hello @KenBurger 

Unfortunately, there is no way to email directly to students' email in Canvas. The announcements and inbox are strictly within Canvas. They could however, get email notifications from Canvas to their emails. It is also depending on the level of notifications defaulted at your institution. 

You may have to email your students outside of Canvas to inform them about the Canvas course. Do you have access to getting a list of your student emails using your institution's SIS (school information system)?

-MaryAnn