well yes - you need your design so that you populate the data also to the
junction table. Nothing embedded within Access does that for you per se...
the classical many-to-many case is a school. Many students, many classes.
The junction table cross references. In general the student population is
fixed (at least once per school year) and the available class set is fixed.
So those two tables, once populated, don't change much within a semester or
all the action is in populating the junction table.
in your case it sounds like you are actively populating all 3 tables at the
same time. which is ok too - but the junction table is not
autopopulated...your form design needs to figure out an efficient way to
accomplish that from the end user perspective....