http://whatisafreeschool.org.uk/ appears to be working properly. Here's what I see: http://d.pr/i/Bwbm/3HTOos9G
When a domain is registered or altered, there is a process called propagation, where information about the domain name is passed to internet service providers all over the world. This process can take up to 72 hours (though usually much less). During that time, you may also receive a warning message in your browser about "redirect errors". Unfortunately, we have no control over this as it all depends on how often your internet service provider updates their records. Please rest assured that everything is proceeding normally with your domain.
You can continue to update your site while your custom domain propagates, by going directly to your Dashboard, here:
https://wwwdotfreeschooldotcom.wordpress.com/wp-admin/
If you still have trouble viewing the site after 72 hours has passed, please try clearing your browser's cache and cookies:
http://en.support.wordpress.com/browser-issues/#clear-your-cache-and-cookies
If that doesn't work, try clearing your local DNS cache:
http://www.opendns.com/support/article/68
Please let me know if you have any more questions.