Chris Husbands
It is probably an apocryphal story. George Bernard Shaw was propositioned by Isadora Duncan, who suggested that she and Shaw should have a child together. “Think of it!” said the acclaimed dancer, “With your brains and my body, what a wonder it would be.” Shaw thought for a moment and replied, “Yes, but what if it had my body and your brains?”
The story comes to mind in reading the web statement on the government’s proposals for the new primary national curriculum, which tells us that the proposals on algebra are consistent with “the high-performing education jurisdictions of Singapore and Hong Kong”, the focus on times tables draws on the “high-performing jurisdiction of Massachusetts” and the science curriculum is “similar to the approach taken in Alberta and Massachusetts”. 
Unfortunately, despite this whistlestop tour, the draft programmes of study so far developed do not include geography, but the message is clear: different countries have been used as models to benchmark different parts of the curriculum. With so broad an approach to “learning from the best”, surely the results will be exceptional.
In fact, the mechanics of policy borrowing are just as complex as George Bernard Shaw feared the workings of genetics might be. There is attraction in believing that if a practice works somewhere,  it will work anywhere and that the task of curriculum construction is a matter of taking what is done somewhere else and applying it in a different jurisdiction.
If that were the case, education systems would be more alike than they are. In fact, patterns of performance are more difficult to fathom. There are education systems which are higher performing than others:  the Pacific Rim countries score highly on mathematics and science, as does the northern European jurisdiction of Finland. But Singapore (retaining selective schools) is quite different from Finland (wholly comprehensive), and the curriculum is quite different in Korea (high performing and highly centralised) by comparison with Canada (high performing and decentralized). 
Why this should be the case is a matter of fierce debate. Of course, the task of learning mathematics is as culturally invariable as any subject could be, but the context in which it is learnt is not:  the role that mathematics and science play in different cultures varies hugely. The assumptions made about what “teaching” involves vary enormously.   Moreover, the variation in performance between countries, on PISA evidence, is not in the levels of performance of the best performing children but on the distribution of weaker performance: put differently, equity matters a great deal in education system performance.  And this is why it may be more difficult to bolt together the algebra of Singapore, the multiplication of Massachusetts and the science of Alberta.
The lessons of educational improvement are hard ones. As the American scholar – and now chancellor of the Chicago public school system – Charles Payne bemoans in his most recent book “so much reform, so little change”. Ben Levin, the hugely influential Canadian academic – and former secretary for education in rapidly improving Ontario – observes in How to Change 5000 Schools, “teaching and learning practices [are] far ahead of curriculum as a means of improving student outcomes”. No curriculum, really, exists on a piece of paper, but in the day to day challenge of classrooms.