For those of you who call squares, I've found that some can be adapted
to 3 or 5 couples. The visiting couples squares can be changed pretty
easily, like Shoot the Owl. I use Cheat or Swing when there are 10
people dancing.
Also, a square that does not have definite moves for heads and sides can
be changed. One example is Ashley's Star, where everyone is moving all
the time. Star Breakdown is another good one for this.
Jerome Grisanti made a very clever discovery one night when he had six
couples who wanted to dance. He called a square that DID have definite
moves for the heads and side, and he designated the fifth and sixth
couples as "others". So after the heads had done the figure, he had the
sides do it, and then the OTHERS. It's more of a mental challenge for
the caller, but that is one of the perks of calling squares.
Jo Mortland