Sixes and Sevens
Middle schoolers are going nuts right now.
There was no forethought in following our puzzle Fantastic Fours with Fracks in Five. But such machinery, once set into motion, is hard to stop, so here's another puzzle that's on the up and up.
... OK, true story, I went to merriam-webster.com to look up the phrase "at sixes and sevens," but before I could even type in my query, I got served this skybox:
Before we continue, let me give those who sensibly don't want to get caught up in my tangent the puzzles they're here for — thanks to test solvers Andy Stilp and John Sams, and editor Andy Yingst. (Note to online solvers that we're still working on getting the online implementation to work — please check back in a couple of days if you don't want to PDF it.)