Snip.ly is an interesting new web application. Without having to register, you first paste a url address of any webpage into the site. After you click “next,” you will see the page “within” Snip.ly. You can then highlight one section of the text on the page and write a note about it. You’re then given a url address (or can directly email it) of the page “within” Snip.ly with your note “floating” in front.
If you sign-in (you can only do so with Twitter or with Facebook, which eliminates school use of this feature), you can see what other users have “snipped” and said about that same webpage.
There are plenty of other applications that make webpage annotation more feasible for student use (see Best Applications For Annotating Websites). However, Snip.ly may be one of the easiest ways to send an article if there’s just one section you want someone to notice.