What is the name of Professor Dumbledore's phoenix/ (Fawkes)
How do you get rid of a boggart (Ridikulus Spell)
What are Slitherin's House colours (silver & black)
Who was wormtail? ( Peter Pettigrew aka Scabbers the rat)

Hausfrau - if you want a guineapig, ds1 will happily 'test' your guiz for you!  He's mad on HP and has read all the books many, many times.  And remembers loads of obscure facts.  But struggles with the degree of detail on the Newsround website questions.