HEYHEYHEY (64D: With 64-Down and 64-Down, Fat Albert's catchphrase) I liked it!
It's a bit of a silly theme, but I really enjoyed it. Many of the theme answers made me smile, and there were a ton of them. I count 16! Is that a record?
There was a little weirdness in the fill, with ARTI (16A: Introductory drawing class) (But I don't mind, really, when an I or a V, say, serves double duty), ATTA (39A: Lead-in to girl), and TBTEST (33A: Med. exam involving an injection into the forearm), and I don't really like WEEUNS (42A: Tots), but, well, I'm giving it all a pass.
I liked the simplicity of 19A: Not found (LOST), 45A: & (AND), and 20A: Play in the N.H.L. (SKATE), and the directness of 8D: "Green thumb" or "purple prose" (IDIOM). I'm sure Huygens will enjoy mention of the COSMOS (9D: Universe), and I find it reassuring that after the napalming on Saturday, DRESDEN is now the 10D: German city rebuilt after W.W. II.
Very fine Tuesday.