Ann, PFW, Project Feeder Watch is a Cornell labs citizen science project.
http://feederwatch.org/ is the website. It costs to join so many don't do it. You count birds at your feeders 2 days a week from November to early April for as little as under an hour total time. This was my 9th season counting. There's a form to use for counting and you input the data online. I love going back and comparing what birds I saw at the same time for different years. (And I don't have to keep a spreadsheet, they do it for me.) The hardest thing is to only count 1 cardinal (or whatever species) if you see a male and female separately, but not together. You do get used to it though.
