The Oxford Phonics Dictionary has 'ure' as representing /yoor/ for words such as pure, cure, mature.
The new National Curriculum Spelling Appendix has 'ure' representing /ch/er/ for words such as measure and furniture.
DDs school spelling scheme places 'ure' with 'er' 'ur' and 'ir' as they sound in the middle of words (i.e. /er/.
We use a variety of ways to pronounce the 'ure' spelling:
/ch/or/ for immature
/yer/ for pure or insecure
/ch/uh/ for creature
/zj/uh/ for enclosure
The schools spelling scheme makes the least sense to me, but even the other two don't really work for the way we pronounce these words. To me creature ends in a schwa - again can't find any validation for this. Perhaps we just speak with a funny accent 
So, for those with the patience and understanding to get this far my question is shall I bother to go through this with DD (I can see I'm being very pedantic about it)? Especially as it means making up a sound /yer/ that doesn't seem to exist in phonological lexicons (not sure about the terminology, but hopefully you know what I mean). Or shall I just leave it, despite the fact that the obsolete spelling scheme doesn't follow synthetic phonics, and seems to lump words in randomly when they have a vaguely similar spelling with little regards to sound correspondences.