My daughter recently turned two. Here's how I made it Mainstream Green, and suggestions to help you do the same for your next party:
Use things you already have. My girl's party was teddy bear themed, so we put groups of her teddy bears on the tables and an over sized bear to greet the guests.
Find natural rubber balloons, which are biodegradable. (Remember to closely supervise young children playing with balloons, and take away any that pop.)
Use beach balls instead of balloons. These cute ones would be great for a tropical theme (maybe next year). They would also make nice take home favors.
Skip the crepe paper and paper table cloth. No one really remembers those, anyway.
Make the snacks double-duty. Find snacks that go with the theme, and put them out in bowls. We used Teddy Grahams and gummy bears. Colored Goldfish crackers would be great for that tropical theme mentioned above.
Let's NOT do lunch - or dinner. A morning or afternoon party with snacks, cake and drinks is just fine. Since my daughter naps in the afternoon, we planned a light brunch.
If you can, Enlist help for the food. We are fortunate to have three sets of grandparents all willing to help with their granddaughter's party. If you can get help, use it!
Keep the menu simple to prepare, and more healthful, too. In my experiences, fresh fruit or a plain fruit salad goes over better than any whipped cream or marshmallow fluff concoction. And it's easier to prepare, too. Just keep an eye out for what's in season, as fruit can be pricey.
Location, Location, Location
Hold the party somewhere centralized. Both my husband's family and my family live about 30 miles from us. It made more sense for us to drive that distance than to have everyone come to us. In green terms, we had one vehicle driving 30 miles instead of six vehicles.
Use the phone. I have graphic design experience, so this was a difficult decision for me. But in the name of all things green, I skipped the paper invites and picked up the telephone. Just be sure the guests know that the call is the official invite.
If you must do paper invitations, use postcards. You'll save on postage and use less paper, too.
The typical birthday party leaves parents with an empty wallet and a bag of trash. Concentrate on what's really important (for me, celebrating with all sides of my family) and cut the unnecessary. By thinking outside of what is "expected" for a kid's party, you can save cash and be a little greener.