Hiya,
Remember to go to:

-customize
-settings
-permissions
and click 'give admin rights' for kim.fitchew@barnet.ac.uk

You and I have admin rights all others have 'author' rights only.

Don't forget to accept all your invitations. Then each student will make you an author (whereas on your blog only you and I are authors 'with admin rights'
Thanks,
Have a good day!
Kim