Really new, I just started the lessons.  When do we learn C Major?  Did I miss it?  We learned G, Em and Am then we started the lesson on full, half and quarter notes.  On the lesson with quarter notes they want us switching to C Major but we were never taught that.

Also, when we were taught Am they have us using all 6 strings, but then on the quarter note lesson the don't play they top E string. 

Just a bit confused.