One concept that I did feel kinship with early on was her belief that children's lessons should be kept quite short. About a week ago, I decided to start timing our instructional time just for informational purposes. The first block of the morning is always davening, torah stories, Hebrew songs, plus other Jewish studies. That takes about an hour, 30 minutes of which the children can quietly draw while they are listening. What I was a bit astonished to discover is that most of our other subjects (Hebrew writing, Hebrew grammar, English printing, English grammar, spelling, composition, and math) only take 5 to 8 minutes per lesson! Reading (English and Hebrew) (5x/week) and history (2x/week) each take 15 minutes per session. Science and art take longer just because of the nature of the subject.
And yet, even with lessons this short and plenty of time taken for summer activities and play, we are already pretty far ahead of schedule compared to what I estimated we would complete in the first two months of our year (our learning calendar runs July to June). I think optimal focus (short lesson) + optimal instruction (tailored completely to the student) = a great deal of information being processed in a very brief amount of time.
There is another Charlotte Mason suggestion that I have always used in our printing work—that it is much better for a student to write three really good Bs, then to write a whole page of them getting sloppier as they go. Again, there is the principle of instilling a good habit, in this case of making letters that are very well-formed. This takes advantage of that absolute focus that comes when a student is fresh and the length of the lesson hasn't allowed their mind to wander off.
Miss Mason recommends that lessons for elementary school children should be 15-20 minutes long. For junior high it should be 30 minutes, and for high school, 45 minutes. Even the youngest students should have 15 to 21 subjects to study (we have 20, thanks to all of our Jewish studies!). I'm sure our lessons will naturally lengthen as the material demands it, but for now it's working really well, and I absolutely believe in the effectiveness of (surprisingly) short lessons.