Did I hear some one call?
Well, I obviously know the knitting rhyme, I sometimes forget the purl rhyme. :eyebrow2:
I agree with using big needles and thick yarn. You might consider a braided yarn or cording so it is more difficult to split. Using US size 10 and bulky yarn can make a quick swatch into a dishcloth or a longer knit into a scarf.
Children want fast results, so I'd let them pick from flat designs for hats, scarves, dishcloths, wash clothes, place mats, napkin rings, and such.
Avoid blankets (unless they are doll sized) or anything that is big.
Good luck. Crossed Fingers