my second graders (and third grader too, actually) most all yucked out their
crayon resist too. We tried both tempera cakes and water color cakes. We had
a page of leaf rubbings and they basically covered the leaves so that the
crayon didn't show any more. I think the problem is that they don't make a
thin enough wash and they use so much paint that they build up a layer that
stands on top of the crayon. This was even after looking at an example and
practicing thin washes on a separate paper, and watching me apply a thin wash
that the crayon could actually resist. For my next try, I might use thinned
liquid tempera that I make into a wash consistency-- but then they don't have
to learn that skill themselves. I don't know. . . Almost every thing I try
with second grade is turning out too hard.