We have started putting together a list of add-ons useful in educational settings:
https://plone.org/community/edu/intranet/ploneedu-addons [login required to view]
That page is still being developed, so in the meantime I have posted this list of add-ons we use at UW Oshkosh for our current Plone 4.3 Zope:
https://plone.org/community/edu/intranet/plone-4-3-add-ons-used-at-uw-oshkosh [published]
Why are there two collective.easyslider eggs within the buildout?
Within an active project we are currently testing collective.taxonomy as a multilingual category management for a website in 10 languages with close to 100 categories within the migrated content. Although the Plone categorisation/tag mechanism is powerful we needed a multilingual mechanism that did not reproduce every item (taxonomy uses the VDEX system - http://en.wikipedia.org/wiki/IMS_VDEX
Just something other's might be considering in a multilingual educational context. not your everyday use-case.
Um, I've removed the duplicate line 
Thank you!
What is this very interesting sounding web site project that requires support for ten languages? Is it educational in nature?
I am still submitting add-ons to the http://paragon.plone.org project... Please do so if you really like a particular add-on!
No worries, two pairs of eyes are better than one 
I thought the Paragon nominations were closed already! thanks for the reminder.
We are developing a Plone site for an NGO that does peace education worldwide - currently on an outdated version of eZ Publish (www.graines-de-paix.org) - part of the CMF platform we are developing is a series of Dexterity content types which contain 'peace ressources' for teachers/parents/anyone to use to assist in transmitting a culture of peace.
These resources will be translated by volunteers into 10+ languages post-launch using plone.app.multilingual and collective.taxonomy - I plan on writing more about this site once we surpass the development phase and have more than just a moment to breath.
As such our use-case is not that of a 'traditional' educational facility but we work in the education and collaborate with UNESCO, UNICEF, and national educational institutions.
Kim - these are both really helpful - thanks !
Having been burned by a carousel-like add-on some years back I'm sensitive
to ease-of-removal for the quasi-non-technical user. I'll be glad to work
with you to annotate the list with some thoughts about how to remove the
products you don't like.
Wm.
===================================
William FennieSilver Spring, Maryland