My little girl requested a Mad Hatter tea party for her birthday. Here are a few ideas:
Greet guests with a simple reminder of the type of party planned at the front door to set the mood.
Buy cheap black top hats from any online party store. Allow children to decorate their own.
Once they have finished their hats, party favors can be given in the form of costume embellishments. For small children feather boas can be cut in half to save on cost. Glasses and other jewelry can be found for very inexpensive at party stores.
Then set the scene for the party theme. Often times items around the house work for most occasions. Just add props for the appropriate theme.