Hands down! This is the very best bookmarking site there is.
Sure it can bookmark, but it can also mark— Need to highlight the text? What color?!! Want to add notes, easy! Want to bookmark the page for later, and save the markups you’ve done? Yes! Want to send a link to your colleague or partner in an assignment? You can easily email them the link to it. What’s more, it is a browser extension so you can use it seamlessly with not much more than a click on any website you are on.
To show the magic of what it can do I’ve pasted one of my favorite sites on a summary of elephant intelligence below.
Here is the same site after I used Diigo:
This will revolutionize the way research is gathered on the web. What’s more Diigo has a special educator account available. To get the educator account first sign up for a free account and then apply here. In this account you can create student accounts (yes, you can upload a CSV file) even without email addresses. You can also put your students in groups.