Della,
Some suggestions. Add a few more tags to your poll post including maybe something like education, or similar. You should be able to find more that are useful on the list already.
I would also tag/mention a couple of the other education related groups/places using the @ And the place Name. target the groups you think are most likely to have viewers that would respond....it will show up on the tagged list of content. Don't overdue it or it can have the opposite effect. I went to the "Places" tab and filtered by "Ed" as a start to see some of the other locations that might be interested.
With it only being in the grace group, only those that are following that group will tend to see it. Might be too small or a group at this time . (And yet, maybe the 128 members are the same as in the other groups ??) but Education has 231 followers at this time.
(edit...iPad doing strange things this am)