This bird nest is even quicker and easier to make. It can be found on FamilyFun.com
If you dont not want to make a fake birdnest, how about something that helps the real birds in nature.
FamilyFun.com and thtough it could be fun depending on how you go with your theme.
dtkl-cards Some of the themes that are a available are flowers, spring and earth day.
Another game could be some sort of fishing game where you have a pole with a string and try to catch a fish, or a treat etc..
If you would like to play a pin the tail type of game, you can do variations like pin the wing on the bug, pin the apple on the tree, pin the flower on the stem etc.
Some snack ideas that would be good in the classroom, would be food made from nature like carrots, strawberries, grapes, and apples.
What is nice about doing a nature party is there are so many things in nature that you can chose from and so many different ways you can go with a theme. You could make your party all about bugs, all about growing seeds, all about being green or many, many more.