Jonathan Carter and Stéphane Graber are retiring as Edubuntu's project leaders. After 14.04 they decided to move to LTS-only releases as they began working on other projects, but with 16.04 LTS due next month, they decided they can't invest the resources to make a new release.
Thus no new release of Edubuntu is planned but they will be looking to maintaining Edubuntu 14.04 LTS through April 2019.
It looks like the last time I fired up Edubuntu was the 7.10 Gutsy Gibbon release.
They aren't calling Edubuntu dead quite yet as they do welcome other contributors to take over the project.
Graber wrote in a mailing list post, "That's not to say that Edubuntu is dead, at least not yet. While Jonathan and I will solely focus on fulfilling our promise of support for Edubuntu 14.04 LTS, new contributors are absolutely welcome to take over the Edubuntu project and shape it to their liking. The two of us will be happy to sponsor any Edubuntu related uploads, will help new contributors get Edubuntu membership and then hold elections to setup a new Edubuntu Council which would finally take the whole project over from us. Should none of that happen by the time Ubuntu 17.10 is released, Jonathan and I will ask the Technical Board to revoke Edubuntu as an official flavour and will be removing any leftover packages from the archive, remove our seeds and any cdimage build integration, effectively removing Edubuntu from the Ubuntu release process."