I'm sorry no one has gotten back to you on this subject yet. I think with 1st graders the grades aren't as important
as the work they do and what they learn. I use A+'s, A's, etc because my daughter is very motivated when it comes
to getting A+'s. That being said, I would take the course work and average it out and have it count for half of the final grade.
Then if you do tests and quizzes, they would be averaged out and count for the other half. Once they get to High School,
grades are really important. That's when all they learn in the early years will show up. I hope this helps. It's just what I do.
Good luck!