MindMeister - a collaborative mind-mapping tools that integrates with GoogleDrive
Link to site: https://www.mindmeister.com
Mindmeister allows you to create, edit and share mind-maps online, you can collaborate in real time with colleagues. Mindmeister works beautifully with Google drive and is available as an Drive 'add on'.
You choose between a number of different pre-determined mind-map layouts, including free style, aligned, left aligned, right aligned and org chart. You can add icons, images, notes, links and attachments to the various bubble on you mind map.
Mindmiester is also available as an app for Android, iPhone and iPad.
I could see this being a useful site for students and staff a like to aide them in planning activities and organising research or project based learning