Since I'd already downloaded Jan's pattern I took a quick look and see no reason RH yarn wouldn't work just fine. In fact, I think I have some RH or similar yarn that I'll use and make some for myself. They look to be really quick to knit and as you want to make them for all the kids, simple and quick is good.
Cheating is an option. . . . Cheaters never win and winners never cheat, but smart knitters who want to retain an iota of sanity do, cheerfully. ~~Kory Stamper