Less-academic pupils are also being directed towards some more vocationally-led lessons in construction or web design. The idea is to keep them inside the school gates at Neath's Dwr-y-felin comprehensive.
The work of Mr Stacey and his deputy, Ravi Pawar, in tuning the curriculum to suit the needs of their pupils is not without its critics. But the pair are adamant their approach is the right one.
"We should not be conditioning children to failure just to maintain an outdated curriculum," said Mr Stacey, who has been at the helm for four years.
"I have to be tough. I took business studies out of the curriculum because it was not working."
Consultation by the Assembly government on a new skills-based curriculum for 2008 started this month and is due to end March 30. But Dwr-y-felin, with 1,200-plus pupils aged 11-16, is already ahead of the game.
Since Mr Stacey has been head, pass rates in GCSE at grades A*-G have gone from 82 per cent to 94 per cent. And 69 per cent now get five A*-Cs, a huge leap from 49 per cent when he took over.
This has been achieved by looking at the needs and strengths of every single pupil, he says.
While there is a still a strong academic focus, English and maths classes in the upper school have been made smaller and new vocational learning has been encouraged from the outset. The more academic pupils continue to take traditional courses at GCSE, with foreign languages and social sciences both strong.
But pupils can choose subjects from two flexible option programmes, meaning they are more in charge of what they do.
Attendance rates have improved as disengaged pupils return to learning, no longer daunted by lessons.
Mr Pawar was a member of the Assembly government subject advisory group on English for the new curriculum.
He said: "Teachers have asked for flexibility rather than prescription. The proposals respond to what they have asked for."
One of the proposals is for some texts, such as the Shakespeare classics, not to be mandatory for everyone, making English more accessible. Steve Bowden, head of Porth County community school, in Rhondda Cynon Taf, said changes were long overdue.
"What's important is that we pull all these consultations together," he said. "There is a subject-specific one and a course-related one. We have to make sense of all that."
Gareth Matthewson, head of Cardiff's Whitchurch high school, argued for a change at key stage 3.
He said: "Year 8 does not have the same focus as Years 7 and 9. At Whitchurch we try to get them off to a major school trip somewhere."
Goronwy Jones, head of Cardiff's Baden Powell primary school, said: "The KS2 curriculum was a secondary school model based on defined subject areas that claimed most of the timetable. It needs to follow on from KS1."
Jane Davidson, minister for education, lifelong learning and skills, said:
"A single framework for curriculum, assessment and qualification system from the ages of three to 19 will help to raise standards and widen opportunities."
See TES Cymru leader page 26