How do you plan progression for multiple grades/semesters?

Hi! I’m new to teaching computer science, and I’m loving the resources so far! However, in my school, students can take computer science as an elective any semester. I have an idea for how to plan separate 6th, 7th, and 8th grade offerings, but how should I plan Fall vs Spring semesters? I don’t want students to have to essentially repeat a semester of the course if they choose to take it each semester, but I also want to keep the entry level low since any student could take computer science for the first time at any time. Should I keep whole units together and do a different unit each semester, or should I complete individual chapters and mix units? The latter option looks like it might work for some units, but not others (like interactive animations and games). Any advice is appreciated!

I would really love to see what other people are doing, but in the meantime, here is a link to the curriculum guide. If you look at page 27, it has some different suggestions on ways you might modify the units to better fit different schedules.