rgcsegers on "New pages in Twenty Eleven (child) without dropdwon in menu bar"

When I make a new page in my Twenty Eleven theme it automatically reveales as a dropdown in the menubar. But I just want that for a few pages. The most pages I want to make have to stay in the background of the site.

So how can I make new pages that aren't visible as dropdown in the menu?

Thanks in advance!