Our homeschool group has been doing this for a while. Every year it has been different. We have gone from a very laid back, casual event to a more organized occasion.
Some of the things the children in our group do are:
reciting poetry or scripture,
skip counting or reciting math tables,
reading a report they have written,
displaying a big project and telling about it,
singing a song,
playing piano,
displaying lapbooks and describing what they learned,
narrating a slide show,
reading pages from a book (especially our younger students just learning to read),
making a display of art work,
and/or anything else that they might have done that was interesting to them.
We don't necessarily decorate tables, but just put work out for display for the guests to view.
It is something we look forward to every year. HTH
Emily