With money available for textbooks not even keeping pace with inflation Mr Jarrett knows it's only the hard work of teachers that is ensuring the quality of education doesn't suffer.
Out of a total school budget of Pounds 2 million annually only Pounds 25,000 will be spent this year on books for the 860 pupils at the 11-18 school. And GCSE and A-level textbooks account for the bulk of that.
His school is the only one in the Walsall area of the west Midlands that has seen the percentage of five A* to C GCSE passes rise in each of the past four years. It now stands at 33 per cent.
Before becoming headteacher eight years ago Mr Jarrett was head of science. Then he had a budget for all resources of Pounds 3,000. Since then it has risen by only Pounds 500 for textbooks, exercise books and lab materials.
He said: "It is because the staff have been able to overcome such difficulties that we have achieved the results we have. But the work it puts on teachers is incredible. They rely on preparing their own material and devising new methods of delivery."
In the late 1970s and early 1980s every key stage 4 pupil would have had their own textbook, he says, adding that the idea of youngsters taking away a textbook to complete homework is a thing of the past. Instead staff prepare worksheets.
In its financial plan for 199798, the maths department had a capitation allowance of Pounds 3,505. That included Pounds 1,120 raised from its own sources. Exercise books and stationery cost Pounds 700. A further Pounds 1,460 went on textbooks. There are insufficient funds to spend Pounds 450 on GCSE textbooks and the Pounds 3,000 the department says is needed to ensure a textbook for each pupil.
Meanwhile, the geography department is engaged in a losing battle to save up for new atlases. Each time enough money appears to have been hoarded the books have again increased in price.
Because the Brownhills area has been identified as one of significant deprivation it has qualified for a Single Regeneration Budget grant worth Pounds 46,000 this year, aimed at raising the standard of literacy. These funds have paid for the computerisation of the library, easy-to-read fiction for the library and textbooks for Year 9.
Such additional funds - there have been European Commission and National Lottery grants though not for textbooks - have helped the school maintain a basic standard. But it is still difficult balancing the books.
Christine Hillier, head of English, praises the quality of textbooks on the market, but bemoans the fact she can't afford them.
"Textbooks are so expensive," she said. "So we have to buy a lot of resources we can photocopy. They are not as appealing or as good as the textbooks I would buy in an ideal world.
"It is difficult to deliver English and English literature without good quality textbooks."
While not having sufficient textbooks is frustrating, Christine Hillier believes a bonus is that it makes for more active teaching. "You can't sit a class down and say turn to page 68 or whatever. When we are doing Macbeth, for example, there aren't enough textbooks so I prepare worksheets and notes. "
Mr Jarrett hopes that Labour will start to deliver on its promises to education and is optimistic about the future.
He believes money for more resources is needed - not just for textbooks, but to meet a wide range of needs.
Meanwhile, librarian Jane Lane has recently had to discard around 100 social science books because they were woefully out of date. With an annual budget of Pounds 2,000 for all new library books, it will some years before they are replaced.