Yes, don’t use the Child Page setup. You can un-link each Child Page from it’s Parent in the Page Editor (write down how this was setup so you cam mimic it in next step). Then, create a Custom Menu…add your pages in. Use indent to make a child appear in the menu under the pages they were at. Once done assign menu to theme menu location (Theme support required). Each page when clicked on will still take you to the page, but the URL will be yoursite.com/slug. Speaking of slugs, you can edit the slug of each page also in the Page Editor.
You could even opt for the short link. yoursite.com/?p=id – with permalinks in use, the visitor to this url will redirected to the page’s permalinks url. You can make it even shorter with a URL shortening plugin or service:
http://goo.gl/
You: http://goo.gl/VeANf
I have done this and it is exactly the same as before although I can now type the shortened url and get to my page. Is this what you mean’t?
The webpage in particular is;
http://www.wackynation.com/our-events/reverse-running/backward-challenge
I can now type http://www.wackynation.com/backward-challenge and it works but it is displayed online as the full url. Have I done something wrong or is this what you mean’t?