This looks like a really interesting, and fairly easy, project to build. The problem was, I wasn’t really sure what you could actually detect once you finished it. Luckily, the web site has a link to a PDF that has experiments you can perform with your new radio telescope.

This system is NOT a radio astronomy system to be used for serious sky surveys,
but it is a tremendous starter unit to give you the excitement of detecting the Sun,
your own body radiation or just 300 deg. K tree branches.

DIY radio telescope – Link
What to do next? – PDF Link