Colapsable menu

Hi – was ondering if someone could help me – I have searched the forum and there seems some solutions but non that have workd on the latest wordpress.

I want to be able to put a number of static pages some of the pages wiill have sub pages – at the moment these subpages are shown in a normal list manner on the site – I was wondering if anyone knew how to change this to a colapsable menu so only the parent shows until it is clicked on – once opened any other page clicked on in that group will keep the tree open there. (? does that male any sense)

Thanks for your time