Today's theme gives us an alternative - we can look on the bright side, or we can wallow in negativity. In other words, we can take either side of the GOODNEWSBADNEWS themers.
The themers start slow with GODOWNINHISTORY (17A: Leave a lasting legacy ... or do worse at school), which works well for the positive interpretation, but is kind of tortured as a description of a lowered grade at school. They only go up from there, however, and my favorite is probably the last - DRAWABLANK (54A: Be lucky in Scrabble ... or come up short memorywise). Both happened to me this past week. Hah!
In the fill we've got the somewhat un-Mondayish PRIVATEER (36D: Nongovernmentally owned ship decked out for war) - some folks might be left ATSEA on that one - I know I needed at least a few crosses!
I like the phrase PIPEDUP (44D: Chimed in on the conversation), and the clue for PRO (34D: One giving you the aye?) got a chuckle once I finally figured it out. Sheesh! WAG (64D: Jokester) is an underused descriptor, but I've never really believed in the expression OHO (2D: "Well, whaddya know!"). Does anyone ever actually say that?
Overall, it was a fine Monday. A clever little theme, and not too much to complain about.