*** Note: Khan requested I post this to gauge community response, so please respond if you think this needs to be fixed. ***

Home schooling parent here. I have tried to assign Calculus 1 (not the AP version), to a student (my daughter) as a parent, teacher, and from my daughter's account directly. The course does NOT show in the list presented for selection when attempting to assign, but does exist in Khan Academy. 
NOTE: I have seen in FAQ/KB where other courses are not on this list. Some discussions dating back years, so I doubt this will be fixed, but thought I would put it forward to make you aware anyway.
Thank you for all you do,
Tim
**** Instructions to recreate issue **** 
  1. Sign into student account
  2. Click student name in upper right and click on "Learner Home" in the menu
       2a. Probably done by default, but ensure that "MY STUFF" | "Courses" is currently selected on right column
  3. Click on "Add another course" to the right of "My courses"
  4. In screen that pops up to select course, top section says "Math" - to the right click on "See all (45)". "Calculus 1" does not appear as a possible selection.
       Note: there are other courses missing in math section and in other sections.