THIRTY years ago Margaret Thatcher was elevated to Cabinet rank and earned the soubriquet of “milk snatcher” for ending free milk in primary and special schools.

Now, Cabinet documents for the year, released earlier this week under the 30-year rule, show that Mrs Thatcher could have been even more unpopular - for introducing library charges.

She had been appointed education and science secretary when Edward Heath’s Conservatives won the general election in June 1970. They had taken office pledging public spending cuts of pound;1.7 billion. Other ideas contemplated and discarded included a pound;4-a-week charge for hospital patients.

Mrs Thatcher’s library charges proposal was tabled at the Cabinet meeting of September 15, where she broke etiquette by proposing larger cuts than those outlined. She admitted the charges would be unpopular and two weeks later they were dropped.

The government did go ahead, not without misgivings, with her idea to end free milk, raise further education course fees by 50 per cent and increase the price of school meals (from 1s and 9d to 2s and 5d). Concern was expressed by her colleagues that the combined effect of the meals and milk measures “would not, in practice, reduce nutriton below the danger level, but it might well be subject to adverse comment”.

There was a purpose to Mrs Thatcher’s tactics. She had made primary schools her priority and wanted more money for new buildings. The funding allocation was below that planned by the Labour government and she wanted another pound;37m to close the gap. Maurice MacMillan, the chief secretary, initially offered pound;20m and Mrs Thatcher eventually settled for pound;28m.

Cabinet papers for the first part of 1970 show Labour preoccupied with a teachers’ pay dispute. The issue figured in seven of the first 14 Cabinet meetings of the year, as the government and employers steadily retreated in the face of a campaign of local stoppages, and the teachers’ refusal to accept an independent arbitrator.

They wanted an increase of pound;135 per year (about 8.5 per cent on average), and eventually got pound;120.

For Ted Short, the education secretary, his last few months in office were uncomfortable. As well as battling with the unions, he was piloting a Bill to speed up the move to comprehensive education through Parliament. He was sent hectoring memos from then prime minister Harold Wilson, anxious that the Bill should be “anti the 11-plus, not anti-grammar school” and unhappy that it proposed to outlaw selection on the grounds of “ability and aptitude”.