Hundreds of school inspection reports - some a century old - have been unearthed in the Estyn archives. The Welsh inspectorate now plans to hand over the yellowing documents to the regional archives for public view.
The stash of school reports is a treasure trove of information for historians, starting at a period of Welsh history when boys and girls were segregated in lessons and pupils were known as "scholars".
TES Cymru was allowed to view the reports, which contain fascinating insights into evolving teaching styles, education policy and social trends. They also show how radically inspections have changed.
While today's reports are broken down into individually graded subject areas and go beyond the classroom to look at the ethos and character of the school, at the turn of the last century they were limited to a few casual observations - especially about the "tone" of the school.
At Swansea's Waun Wen County School in 1917, for example, inspectors said of the "boys section" that "work is generally progressive" and "methods of teaching occasionally show inventiveness".
They conclude: "A favourable impression was formed on the whole of the intelligence of the children in the upper classes."
In 1921, inspectors of Lon-Las Council School, also in Swansea, simply said of the infants: "They seem very bright and happy in their work, which is going on very satisfactorily."
They conclude briefly: "The tone of the school is distinctly pleasing."
The reports are also littered with words and phrases far-removed from today's classrooms. For much of the past century, teachers were "masters" and "mistresses"; lessons were "formal instruction"; pupils "scholars"; and - shockingly by today's standards - pupils with special educational needs were "backward", "maladjusted" or "educationally sub-normal".
But although the language may have changed, it seems that teachers today still face the same challenges as previous generations.
The 1949 report from Caernarvon C of E School could just as easily have come from a present-day report on a school in a deprived areas of Wales. It says: "The pupils' unfavourable home conditions and a lack of parental co-operation are reflected in a poor standard of dress and cleanliness and in apathy towards subjects and activities that require continuous and concentrated mental effort."
We might think of dilapidated school buildings as a modern phenomenon, but even in the 1940s and 1950s teachers had to put up with crumbling classrooms and sub-standard amenities.
The 1949 Caernarvon School report notes that "parts of the classroom walls are discoloured by damp". The toilets, in a detached block in the playground, were also in a poor state, with broken flushes, missing wooden seats and no doors.
And spare a thought for the poor teachers at Copper Works County Infants School in Burry Port, Carmarthenshire, where inspectors in 1964 noted that "facilities for hanging illustrative material on the classroom walls are very inadequate".
"The brick surfaces resist drawing pins and much difficulty is experienced in mounting material for display," they wrote.
Just as today, schools and classrooms were often lacking in essential equipment. In 1938 at Llanddarog Mynyddcerrig Council School in Carmarthenshire, inspectors said a number of "old and disfigured desks" needed replacing, and the school had a "dearth of individual reading books in Welsh".
From the 1960s, reports were more detailed and inspectors started placing greater emphasis on balance in the curriculum. For example, the 1964 Copper Works report praises the "attention given to the basic subjects, which was supported by a genuine concern for art, handwork and music".
When Cefn Glas Residential School for girls in Bridgend was inspected in 1977, the inspectors said: "There's a need to look a little more closely at the balance of the curriculum, particularly in the areas of music, drama and dance."
It was discrepancies such as these that led policymakers to introduce the national curriculum in 1988.
The highly critical 1989 report of Penygraig Junior School in Tonypandy vividly illustrates why reform was considered necessary.
Inspectors said there was an "absence of schemes of work in most areas of the curriculum" and a "lack of policy on assessment and recording". Much of the work "lacked breadth and coherence" and able pupils were not working to their full potential, the report says.
This year change is on the horizon with further consultation to overhaul inspections in favour of more self-assessment. By 2010, Wales will have yet another inspection criteria.