Line break in menu?

Hello, on the site: www.lamhotte.fr/ecole you'll see that I have a menu-entry which is somewhat long. I've tried putting in a line break using html in the menu, but new line is way too much underneath which makes the menu look awful...I did this because when I put the last item (access parents) in the menu, it went on a second line, making the menu look awful as well. Is there a way to have a line break and approaching the text (on my site: "classe linguistique" and "9ème classe"), or maybe having less space between menu items so that everything fits? I hope you see what I mean Thank you