I keep reams and reams of tracing paper. I always carry sheets with me on my
"rounds". When a kid needs help and my verbal cues are not helping, I will
take the tracing paper, and put it on their work, repeat the verbal cues
i.e. "have you thought about extending the line", and then extend the line
on the tracing paper to show what I mean. Inevitably they get it visually.
Within a nanosecond I rip up the tracing paper, leaving them with their
mouths open (first time anyway). And then I move on. Kids will always want
that tracing paper, but of course I won't give it to them. The tracing paper
idea works really well on all of those "almosts" that kids do, you know the
ovals on the tops of cylindars that aren't quite ovals, or 2 pt perspectives
that aren't quite working.