K.O.
Hi L.!
If you are going to have a lot of people attend the party, you might want to try looking at the Pottery Barn Kids catalog for ideas. They have, I think, some good ideas on a carnival theme party, etc. You could set up "stations" for games, with small prizes for the kids and adults alike. Food could be themed for the occasion as well.
If he has an interest like Diego or pirates, you could theme the party to that as well with a scavenger hunt, digging for treasure, an animal search party, etc.
Or you could also have a luau, Things should be going on sale really soon for that type of party favors, etc. It might be fun to impart a little summer into winter. Food, decorations, could all be part of the theme. You could have a limbo contest, etc.
These are just a few ideas for you. If you need any other suggestions, etc., please feel free to contact me.
Good Luck!
K.