Journey North is a great resource for Science, and also for Social Studies.  Here are a couple of quotes from the main page of the site:

Journey North engages students in a global study of wildlife migration and seasonal change. K-12 students share their own field observations with classmates across North America.

Widely considered a best-practices model for education, Journey North is the nation's premiere "citizen science" project for children. The general public is welcome to participate.

The site runs a number of different programs at different time of the year that you can get involved in - for free!  All you have to do is register at their site.  Here's what the registration page says:

Once you have registered, you are in the Journey North database and do not have to register for each project separately... If you request an e-mail subscription when you register, you will be notified when each study begins and receive news reports each week. If not, you can find the information on the Journey North Web site.

Here's a short run down of some of the current programs:

The Monarch Butterfly Migration Program has a fall and spring component to it.   News about the 2008 fall program started August 28 and runs until sometime in October or November, but it's not too late to join in.  Weekly news reports for this program are sent to each Thursday.  Even though we are not actually in an area where we will be able to join in reporting Monarch sighting, we can still follow the sightings as they are reported across North America.  One idea is to make your own paper monarch butterflies to place on a map in the area of reported sightings each week.  There are also printable booklets and online slideshows teaching about the life of a butterfly, how to distinquish between monarch butterflies and some look alikes, etc.

The Whooping Crane Program also has a fall and spring component.  News about the 2008 fall program starts tomorrow and runs until sometime in October.  Weekly reports for this program are sent out each Friday.  This is a very interesting program because you "Follow the story of 16 endangered Whooping Crane chicks making their first journey south as ultralight airplane "parents" teach them the way." 

There's also a Tulip Program.  There are monthly, rather than weekly, reports for this program.  Here's what the website says about it:

students plant and observe tulip gardens to track the arrival of spring. They observe and record when their own plants – and those in other school gardens in North America – emerge from the ground and bloom. As students track this one plant type, along with temperatures, day length, and other seasonal signs, they discover how different factors influence the wave of spring. This sets the stage for better understanding our changing climate.

These are just some of the programs that are active right now from the site.  There are other interesting porgrams that start up later in the year.  You can see a list of all the different programs and when they start on the Year-at-a-Glance page.

Let me know if you decide to participate.