elgg or opensocial: can't decide and it is for a school k-12

I'd like to implement a social network for students and开发者_JS百科 teachers. I just can't decide wether to go with Elgg or OpenSocial. I like Elgg only because it is being used by a growing number of online education sites (and I think it integrates very nice with Moodle). But, I also like OpenSocial because it is supported by Google. When I think long term I kind of lean towards Google...

...and there is also Google Apps Education Edition.

Elgg is more a community script, while opensocial is a set of protocols to develop an social website. You probably will be better off with elgg, and it will be easier to install onto a webserver. Opensocial is more a framework and a way to access data, not a one-time community website. If your looking for another option, buddypress.org is also a good wordpress-based social network platform.

The alternatives are not just Elgg (software) and OpenSocial (specification).

Quite a few Open Source projects exist on which a decentralized social web can potentially be built: http://en.wikipedia.org/wiki/Distributed_social_network