Hi Eric,

The ability to assign entire missions is not possible at this time. However, if you tell your students to work on say, the 7th grade Mission, you can track their progress from the class's Progress tab, and toggle between Skill and Student. Here's a screenshot showing this tab:

From here you can see which students need practice on some skills and who are struggling. What's nice is you can change which subject you're viewing with two clicks, with the helpful filters.

I hope this helps, let me know if you have any further questions!