I print off a free daily attendance sheet from Donna Young to keep our required daily record. We don't do grades. I also buy the teacher book at Target in the dollar bin (they have put out the same one for several years now) that has each week divided into six subjects. Instead of subjects I use the three spaces per page for each of my three kids. Then I have nice big squares to fill in what they do each day. I find that is a great way to keep a relaxed/unschooling record of what each child is doing and reading every day.
I bought a $5 teacher's assignment planning book at the local teaching supply store, and it's working wonderfully to keep dates/subjects/material covered straight for progress-report time.