I believe you. I assemble records for my kids on my own even though our state doesn't require me to, and it's a big job, especially when you include all the details.
Teachers should be required to keep records because they are being paid to do it. It is part of their job. But, requiring parents to do so, especially when they want nothing to do with the school system, is all about state control of the children.
40 hours per student? 150 students per year?
Do the math. 40 hours is one work week. There are only 52 weeks in the year.
How tired of taxes do you want to be?