Besides his birthday message from the Queen, he received many cards and calls from former colleagues in the worlds of education and journalism and also from former pupils and staff of Gateway sixth-form college, where he was headteacher in the Twenties.
His daughter Elisabeth Broome, aged 71, said: "We had a lovely evening. My father is in very good health considering his age and enjoyed himself. He often talks about his time on the paper and the friends he made."
Professor Dent was appointed as first acting editor in 1940 and worked throughout the London blitz in a small office in Printing House Square.
He brought with him radical ideas which at times brought him into conflict with more traditionalist colleagues. But a close working relationship with the architect of the 1944 Education Act put him in the cockpit of the century's most important educational reforms.
Joan Simon, who worked with Professor Dent in the early Forties, got her job on the paper after she wrote him a fierce letter; for The TES was not radical enough for her tastes. His response was: "If you think you can do better, come and join me."
She said: "He was one of those people who believed in getting a grip of things. He had tremendous contacts from the board of education through to local authorities and schools. He was a curious mixture of radical and conservative - he wanted to keep the best traditions."
He believed children should participate in their own schooling rather than be mere recipients. When he tried out his theories as headteacher at Gateway, it was too much for his director of education and he was sacked after three years.
It turned out to be a good move. He turned his hand to writing, which led eventually to his editorship. The present TES editor, Patricia Rowan, has described his time at the helm as "the most exhilarating, demanding and influential in the paper's history. The TES became not just a forum for discussion of the nascent 1944 Act but a new kind of educational journal, campaigning for reform thorough enough to last beyond post-war euphoria".
Former TES editor Stuart Maclure, who was first brought into education journalism by Harold Dent in 1950, says he owed him as lot: "a great journalist and a great teacher".
Dent later became education correspondent to The Times, then professor of education and director of the Sheffield Institute of Education and later director of the institutes in Leeds and London.