Wikiversity

Coursera

coursera.org

Wikipedia

wikipedia.org

wikiHow

wikihow.com

Wiktionary

wiktionary.org

MIT OpenCourseWare

ocw.mit.edu

Wikisource

wikisource.org

Wikiwand

wikiwand.com

Wikimapia

wikimapia.org

Wikidata

wikidata.org

Wikimedia Commons

wikimedia.org

Wikibooks

wikibooks.org

Wikinews

wikinews.org

Learn Anything

learn-anything.xyz

Quill.org

quill.org

Wikivoyage

wikivoyage.org

Wikispecies

wikimedia.org

Wikidot

wikidot.com

Wiingy

wiingy.com

Simple English Wikipedia

simple.wikipedia.org

Google Learning

learning.google

ProWiki

pro.wiki

EducUp

educup.com

Coursio

coursio.com

OpenCurriculum

opencurriculum.org