I may have mentioned it earlier, but mac & cheese just does that if you use some sort of butter substitute. It's likely whole-grain macaroni as well, which just misbehaves.
I've never bought whole grain macaroni, so I will take your word on that.
Judging from the weird almost-green color, and visible grease(?), it's probably whole-grain mac with low-grade olive oil in the "cheese".
Schools are pretty much the only market for whole-grain pasta, because no one else buys it more than once.