Academies, trust schools, league tables and national testing - all controversial issues that dominate the education debate in England but simply do not exist in Wales.
Now teachers' pay could be about to join them in highlighting the growing differences on schools policy emerging on either side of Offa's Dyke.
Alan Johnson, the Education Secretary, has asked the School Teachers'
Review Body to consider whether there should be a "more flexible approach", allowing separate decisions about teachers' pay in Wales.
The current situation, is on the face of it, straightforward.
Responsibility for teachers' pay has not been devolved to the Welsh Assembly. Teachers in both countries have the same structure and salary levels, decided in Westminster. But independence over certain issues, such as performance management and staff restructuring, which affect pay, has been jealously guarded by the Welsh Assembly government.
Combined with a different approach to funding the upper pay scale, this means there has already been some potential for variation in pay according to whether teachers work in England or Wales. The point was noted by the review body as long ago as November 2003. Now it seems Mr Johnson is pushing for the disparity to be resolved.
UCAC, the union for Welsh-speaking teachers, is "over the moon" about the prospect of power over pay going to the Assembly.
Gruff Hughes, general secretary, said: "As a union we were set up to fight for an education system separate from England and this would be the completion of our aims. I think there has been a lot of scaremongering that teachers' pay would go down if pay and conditions were devolved."
For the other unions, though, the idea of a more "flexible approach" for Wales conjures up the spectre of regionalised pay that the Government has pushed for in previous years. They believe a more localised system would mean some of their members losing out.
David Evans, National Union of Teachers' Wales secretary, said: "Because Wales is a small economy with a lower average wage, the big fear is this would mean a drop in wages, with an exodus of better teachers over the border."
Mary Bousted, general secretary of the Association of Teachers and Lecturers, believes that in the long run teachers outside Wales could also suffer.
"There is always the danger of a domino effect, with lower pay spreading to some areas of England," she said. But like Chris Keates, her NASUWT counterpart, she believes it is Cardiff rather than Westminster that is to blame for pushing the issue back on to the agenda.
"The constant desire by the Welsh Assembly Government to do things differently, although not necessarily better, with regards to pay and conditions has generated increasing difficulty, tension and frustration,"
said Ms Keates.
"The review body has commented on this previously and the Secretary of State has little choice but to raise the matter for consideration."
Teachers in Wales fear giving the principality extra flexibility over pay would inevitably lead to Welsh salaries falling behind.
Anna Spokes, who works at Archbishop Rowan Williams Church in Wales school in Caldicot, Monmouthshire, said: "Schools in Wales have funding problems and it is due to get worse. If we had our own award, the pressure would be to hold down pay."
The Welsh Assembly government denies any desire for power over teachers'
A spokeswoman for Jane Davidson, its education minister, said she never acted without consulting the views of people in Wales and had detected no appetite for devolving the responsibility.
Nevertheless, the Government of Wales Bill passing through the Westminster could soon make it easier for such a transfer of powers to take place.
When it becomes law, there is likely to be pressure from devolutionists to grant the assembly more powers and some suspect that Mr Johnson is acting now so that the issue of teachers' pay can be settled in advance.
But Ms Bousted has a blunter message: "It was inevitable this was coming and if the Welsh Assembly government doesn't want it, then it had better start doing a lot more to implement national pay and conditions."
ENGLAND: EDUCATION SECRETARY HAS FINAL SAY
The Education Secretary makes final decisions over teacher pay and conditions after receiving recommendations from the independent School Teachers' Review Body.
The review body will receive a remit letter from the Education Secretary, like the one that was dispatched this month, setting out the issues it must consider.
It then takes written and oral evidence from interested parties including unions, employers, the Government and school governors before writing a report setting out its recommendations.
In recent years, the Government, several "partner unions" and the employers have submitted pre-agreed joint evidence to the review body.
This partnership emerged from the workload agreement signed in January 2003, which has cut teachers' administrative burden and given them more time to plan and assess lessons in return for a bigger role for support staff.
Classroom teachers start on a six-point main scale from pound;19,161 to Pounds 28,005 and normally move up a point every year. Experienced teachers can then cross the "threshold" to reach the upper pay scale, providing they can demonstrate they have met certain standards. This three-point scale starts at pound;30,339 and goes up to pound;32,628. Progression can take place every two years but depends on assessment.
Classroom teachers can receive annual teaching and learning responsibility payments from pound;2,250-pound;11,000 for duties such as heading a department.
Heads, deputy and assistant heads are paid on a 43-point leadership scale ranging from pound;33,249-pound;93,297.
Experienced staff who do not wish to take on management positions can become advanced skills teachers paid on a 27-point scale ranging from Pounds 31,491-pound;50,238. An excellent teacher scheme for those who do not wish to undertake the outreach work of advanced skills teachers is proposed to provide a salary of pound;35,874 from September. Three higher pay bands operate for all the above to compensate for higher living costs in inner and outer London and areas on the fringe of the capital.
In inner London, the main scale goes up to pound;31,749, the upper Pounds 38,916, the leadership pound;99,585 and advanced skills pound;56,526.
Teachers' pay and conditions have not been devolved to the Welsh Assembly and so in theory are the same as for those English teachers outside London.
But guidance is devolved to some extent on issues not relating directly to teachers' pay, such as performance management, continuous professional development and staff restructuring.
This has led to some minor variations. For example, the deadline for schools to draw up new staffing structures, and introducing teaching and learning responsibility payments, was three months later in Wales than in England.
The fact that school budgets are set separately in Cardiff and Westminster can also lead to practical differences in pay.
The Welsh Assembly proposed not to set cash limits when funding upper pay-scale progression, for instance, and there are no advanced skills teachers in Wales because Assembly members decided against funding them.
NORTHERN IRELAND: PARITY IS UNRAVELLING
Education has been a devolved function since the province became a separate entity in 1920.
Since then there has been almost complete parity with England on teachers'
pay. This is because, until the Good Friday Agreement of 1998, the government of Northern Ireland, was either under direct rule from Westminster or the control of Unionists who sought to undermine devolution by reproducing Westminster laws line by line.
But since 2000 and the introduction of the upper pay scale in England, that parity has begun to unravel. Wrangles over the same system in Northern Ireland delayed its introduction by two years. It was only backdated by a year, leaving experienced teachers lagging behind their English counterparts. They have also failed to benefit from the workload reductions enjoyed in England and Wales. The Northern Irish version of the workforce agreement - the Curran review - has still to be implemented due to a lack of funding.
This in turn has meant the changeover from management allowances to teaching and learning responsibility payments (TLRs) has yet to take place, although allowances were frozen in 2003.
SCOTLAND: MCCRONE GAVE A 23 PER CENT RISE
Scotland has always had its own teachers' pay arrangements. The year zero for the current system was 2001 with the introduction of the McCrone agreement.
It introduced workload reforms designed to limit teachers' hours to a 35-hour week and set up the Scottish Negotiating Committee for Teachers made up of unions, employers and government.
This new tripartite pay negotiation system meant central government, by now the Scottish Executive, was given a clear role instead of its previous shadowy existence pulling the strings of local government employers.
Its first deal in 2001 brought a 23 per cent pay rise for teachers over three years and a new, flatter management structure. A second, in 2004, delivered a 10.43 per cent rise over four years.
A six-point main scale ranges from pound;23,316-pound;31,008, with teachers usually progressing a point every year. A six-point chartered teacher scale can bring classroom teachers from pound;31,968-pound;38,013. But to qualify they must take a masters degree-style qualification which can take four years and cost up to pound;8,000.
Heads and depute heads are paid on a 19-point scale ranging from Pounds 38,343-pound;74,844 according to their position, the size of their school and its level of deprivation.