As with other subjects that I teach the kids together, I have 2 kids doing the same level together.  This means that my oldest daughter was in 3rd grade when we started Prima Latina and my 2nd daughter was in 1st grade.  I had really no expectations of the 1st grader keeping up, but she did!  We did Prima completely orally and never used the student text.  I made up my own flashcards so they could at least see the words spelled and they would do Latin flashcards in the car when we did car-school.