I have an exam coming up and am worried about this piece, i find some of the notes don't sound, maionly the D's. My Teacher said it was my reed, and shaved it down , but now it just squeks over the break, my sax teacher said to have a thicker reed!

Does anyone have any tips on reeds and just how to practise the piece, i find it really difficult

I am going to guess you mean altissimo D.

You need a good reed to cope with the altissimo register, make sure it has no splits in it, and that it's not gone too soft.

Practice Ds in isolation at first. I and others very recently left some high note advice in Viva Woodwind (High Clarinet Notes is the thread you need), have a look at that.

The piece in general isn't easy. Practise it slowly at first, with a metronome to make sure that you are in time. I would start really quite slowly, and make sure that every note sounds. Gradually build up the speed until you are comfortable, always making sure that your notes are sounding and it's even. It will eventually get to the correct speed. Although it seems like it will take forever, blieve me, you will spend a lot more time sorting it out if you don't learn it slowly than just doing it slowly in the first place!

About reeds, I can't offer much advice, but go with what Barry said. What strength reeds are you using? I would say, and I'm really no expert, you would need at least a 2.5 Vandoren to get a decent sound out of the altissimo register. An alternative would be to use a Mitchell Lurie 3. I find they make really nice soudning tones in the upper register compared to vandorens, but then I just generally don't like vandorens anymore.

Good luck with it. PM me if you need any more help; I haven't got the music with me at the moment, but I can get it back off the friend I lent it to or look at it at school should you have any more problems.