Every region of the country is home to a unique set of birds, amphibians, and other wildlife. Timing is important, too. Both surveys need to occur when the male birds and frogs are calling, usually between March and July. This site provides links to several other great sites with teacher activities and projects. Once you have learned which birds and frogs live in your area, it's time to identify them.
Most surveys rely on sight and sound to determine animal populations.
You've picked a site, and you've determined which species live there. Make a general map of your site. Keep these accessible, but make sure they aren't too close together - you want to survey distinct bird or amphibian populations at each point. As a rough guideline, keep survey points at least half a mile apart. Mark the survey points on your map, so that you can recreate the survey next year.