A middle-school history teacher once had me memorise the classical Greek alphabet (without diacritics or ligatures, just the 24 uppercase and lowercase letters, including both lowercase forms of Sigma) 4 at a time. Each weak, I'd recite the entire alphabet up to what I had learnt, completed after 6 weeks.

This was largely useless for history but has been helpful for me as a mathematician.

I learnt the modern Hebrew alphabet in high school, using a song (to the tune of Frère Jacques) that a Jewish friend had learnt in shul, but I really only learnt the names. Later I learnt the Russian alphabet by brute force; now I'm back to Hebrew and working (but not hard) on getting the shapes of the Jewish script.