My children are at a private IB school in Australia, our local public school offers the PYP as well. Our maths standards, for example, include the IB guidelines and the Australian National Curriculum (which if I understand it all schools must meet). Both my boys received differentiated maths instruction both in the regular classroom and outside with a specialist enrichment teacher.
FWIW, my children do very few worksheets. There is not a lot of testing, NAPLAN being the exception (unavioidable). I think they spend a little bit of time each day the week before preparing for it (minimal in my mind).
We did an extensive search of schools, and have not found one that would work better for us than the one we are currently using. Not to say it is perfect, but I have yet to find a perfect school!
Let me know if I can be of any more help.
