We are in Mass too and I'm here to tell you that you're overthinking the whole logging of hours thing. I always write on our homeschooling ed plan something to the effect of "We homeschool year round [this is true] and thus the hours of education easily exceed the 900 hours required by the State of Massachusetts." If you keep any kind of log or decent portfolio, very few districts will call you on it or ask for a minute-by-minute breakdown--and, in fact, asking for a minute-by-minute breakdown would be exceeding their mien if you can provide a portfolio that shows your child is up to grade level.
Also, keep in mind that gym (phys ed) is part of those 900 hours, and that exercise=gym. At the VERY least, you can count those weekly farm trips as gym. And honestly, for a six year old, I'd be counting any farm trip as ecology/science on top of that. Schools count field trips as educational hours, so shouldn't you?
An easier way to log hours is to "post-plan" instead of pre-plan. At the end of the week, sit down and think about everything (whether overtly schooly or not) your child did. Then write it all down using "educationese" wording. When your kid is a little older and can read and write, she can even do this herself. For instance, here's what my 13yo recorded for last week. Note that only the math book is actual "curriculum"--the rest was just stuff she happened to do/learn and thought to write down after the fact.
Life of Fred: Pre-Algebra II – pages 14-21.
Karate class: 1 hour.
Watched Modern Marvels: The Telephone (documentary).
Learned about: astrological signs, gerrymandering, alternative voting.
Dance team practice: 2.5 hours.
Community volunteer work: 6 hours.
Vocabulary: Latin roots for “celestial” and “lunar”.
Learned a French phrase.
You do that every week, and at the end of the year submit the entire loooooooooong list to the school, I guarantee their eyes will bug out after about the tenth entry and they'll stamp their approval on your letter of intent. You are underestimating when and what your child is learning, and overestimating the school district's interest in the minutiae of your homeschooling schedule. Trust me.
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