We did DD1's 6th party in-house. We have a lifestyle property, so we just advised parents to send gumboots along so the kids could run around outside.
The main entertainment was decorating their own biscuits. I baked big round choc chip biccies, made icing in a number of colours and put them out with bowls of lollies. The kids loved decorating their own biscuits (even the boys) and they biscuit become part of the party bag.
With past parties we have hired a face painter/entertainer. Always popular with the kids.
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