wbryce - the best thing you can do with the Met exam is to apply the theory to the weather outside the window. Go to
http://www.metoffice.gov.uk/aviation/ or
http://www.avbrief.com/ and look what's on offer, especially the METARs, TAFs, synoptic charts and Forms 214 and 215 (low level wind and wx) and compare them to what's the wx is doing. Look at how the frontal activity and isobars on the charts relate to the METARs and TAFs. It's a subject you can practice every day. Get to grips with the information that you'll actually use as a pilot, and the exam is a walk in the park.
As for the 0 of 6, we can all sympathise - anyone who has done a PPL in the UK has been there (I managed 0 of 11 this time two years ago, and another Goodwood based PPRuNer once known as Speedbird252 took something like 18 attempts to get his QXC recently). It's a hard time of year to learn, but it gets better...