Hypothes.is is a free social annotation tool which allows users to discuss, collaborate, organise your research, or take personal notes. Annotating can be public and open to anyone, confined to small groups or used by individuals.
What does the Hypothes.is software do?
The elevator pitch is easy.
“Visit a web page, then select some text and annotate with comments or tags. You’ll see those annotations when you return to the page, and so will other Hypothesis users.”
The software leverages annotation to enable sentence-level critique or note-taking on top of news, blogs, scientific articles, books, terms of service, ballot initiatives, legislation and more. It has been summarised as “a peer review layer for the entire Internet.
Annotation types
Highlights
A highlight is the digital equivalent of swiping a yellow marker over a passage of text. It anchors to its selection in the document, and quotes the selection, but there are no comments or tags. A highlight is always private (“Only me”), which means only you can see it, and only when you’re logged in.
Annotations
An annotation is the digital equivalent of a marginal note. After making a selection, you use the popup New Note control to create this type of annotation. Like a highlight, it is anchored to the selected text which it also quotes. Unlike a highlight it includes extra stuff that you add: text and/or tags. The annotation can be marked so it’s visible to everyone or as “Only me” to keep it private
Page Notes
A page note is like a social bookmark: it associates comments and/or tags with a document without anchoring that information to a passage within the document. A page note isn’t selection-based. You create one using the New Note control on the Hypothesis sidebar’s vertical toolbar. As with an annotation you add text and/or tags. Again you have the choice to make the note public or private.
Replies
Unlike a highlight, an annotation, or a page note, a reply doesn’t refer to an annotated document. Instead it refers to one of those annotation types, or to a prior reply. You use the Reply link to create a reply. Like other annotation types the reply can include text and/or tags, and must include one or the other.
10 ways to annotate with students
1. Teacher Annotations
Pre-populate a text with questions for students to reply to in annotations or notes elucidating important points as they read.
2. Annotation as Gloss
Have students look up difficult words or unknown allusions in a text and share their research as annotations.
3. Annotation as Question
Have students highlight, tag, and annotate words or passages that are confusing to them in their readings.
4. Annotation as Close Reading
Have students identify formal textual elements and broader social and historical contexts at work in specific passages.
5. Annotation as Rhetorical Analysis
Have students mark and explain the use of rhetorical strategies in online articles or essays.
6. Annotation as Opinion
Have students share their personal opinions on a controversial topic as discussed by an article.
7. Annotation as Multimedia Writing
Have students annotate with images and video or integrate images and video into other types of annotations.
8. Annotation as Independent Study
Have students explore the Internet on their own with some limited direction (find an article from a respectable source on a topic important to you personally), exercising traditional literacy skills (define difficult words, identify persuasive strategies, etc.).
9. Annotation as Annotated Bibliography
Have students research a topic or theme and tag and annotate relevant texts across the Internet.
10. Annotation as Creative Act
Have students respond creatively to their reading with their own poetry or prose or visual art as annotations.
Further detail here on the Hypothes.is blog
Other useful resources
Sue Beckingham
Social Media for Learning 
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