Thank you all so much for your thoughtful insights. I truly value
this group. As a first year teacher it is very comforting to know
that there are so many other art teachers who are so supportive and
eager to share.
I ended up deciding to continue with the planned lesson. In our
previous class period my students had made their own scratchboard
surfaces and this week they got to start scratching their design into
them. I had been having a really hard time making a decision about
whether or not I should change the lesson to do something more
therapeutic - but I am happy with my decision because the students
were really excited to begin working with the scratchboard and I
think they had been looking forward to it.