Early school years are mostly memorization, with some understanding. Understanding should be the focus in later years, after a solid foundation is established.
My kids are in first grade, and I'm very surprised by the level of home work they have (French immersion school, homework in English).
You mentioned Advanced CS students, I would like to change the topic to early grade school students:
Memorization: Words and numbers, the basic tool kit - not a small set of tools either.
Understanding: Story structure, addition/subtraction (math in general). These also hinge on memorization, a concept forgotten is not useful (for me, calculus, and the statistics and actuarial risk concepts based on calculus - which I no longer remember, my forgetting was actually on purpose...).
I appreciate the comment but wanted to bring the conversation down to the... level of the submission.