Not a course, as such, but reading “Measurement” by Paul Lockhart, of “A Mathematician’s Lament fame. I’ve never read anything that so clearly communicates and

Not a course, as such, but reading “Measurement” by Paul Lockhart, of “A Mathematician’s Lament fame. I’ve never read anything that so clearly communicates and leads you into a state of mind that COMPELS you to prove mathematical conjectures from first principles. I found myself furiously sketching geometric proofs and simplifying algebraic conundrums with an enthusiasm I haven’t experienced in decades. And a course on sewing for beginners and continuing Japanese.