GENERAL
Website: https://goalbookapp.com/
Website: http://www.ck12.org/
Free Android Phone app: https://play.google.com/store/apps/details?id=org.ck12.app.practice
Free Android Tablet app: https://play.google.com/store/apps/details?id=org.ck12.app.practice
Google Chrome app: https://chrome.google.com/webstore/detail/ck-12/ilmbnmigihncgeckjgmkehcgkdeohkhl
Free iPad app: https://itunes.apple.com/us/app/ck-12-free-fun-way-to-learn/id909343639?mt=8&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/ck-12-free-fun-way-to-learn/id909343639?mt=8&at=10l6SU
Free Android Phone app: https://play.google.com/store/apps/details?id=com.fusionprojects.edmodo
Free iPad app: http://itunes.apple.com/us/app/edmodo/id378352300?mt=8&uo=4&at=10l6SU
Free iPhone app: http://itunes.apple.com/us/app/edmodo/id378352300?mt=8&uo=4&at=10l6SU
Website: http://www.edmodo.com/
Google Chrome app: https://chrome.google.com/webstore/detail/edmodo/fpcdidgjjebefhmlhjlgnkahlimgaemc
Free Android Phone app: https://play.google.com/store/apps/details?id=com.schoology.app
Free iPad app: https://itunes.apple.com/us/app/schoology/id411766326?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/schoology/id411766326?mt=8&uo=4&at=10l6SU
Website: http://www.schoology.com/
Website: https://quizlet.com/
Edmodo app: http://www.edmodo.com/publisher?uid=507204
Free iPhone app: https://itunes.apple.com/us/app/quizlet/id546473125?mt=8&uo=4&at=10l6SU
Google Chrome app: https://chrome.google.com/webstore/detail/quizlet/bgofflgeghkhocbociocnckocbjmomjh
Website: http://www.instagrok.com/
Free iPad app: https://itunes.apple.com/us/app/instagrok/id777873941?mt=8&uo=4&at=10l6SU
Google Apps for Education app: https://www.google.com/enterprise/marketplace/viewListing?productListingId=17789+13349884249762973052
Google Chrome app: https://chrome.google.com/webstore/detail/instagrok/flonaffkffjppejcafgpdgilebfikemd
Edmodo app: http://www.edmodo.com/publisher?uid=7493337
Free iPad app: http://itunes.apple.com/us/app/inkling/id379351586?mt=8&uo=4&at=10l6SU