Pope Benedict XVI kisses the head of a boy today as he arrives for a celebration of Catholic education at St Mary's University College, Twickenham, London. The pope is on a four-day state visit, the first by a Pope to Britain.

LONDON — Thousands of cheering Catholic schoolchildren feted Pope Benedict XVI on his second day in Britain today, offering a boisterous welcome even as the pontiff urged their teachers to make sure to provide a trusting, safe environment.

It was the second time in as many days Benedict referred to the church sex abuse scandal, following his acknowledgment Thursday the Roman Catholic Church had failed to act quickly or decisively enough to remove pedophile priests from ministry.

Polls in Britain indicate widespread dissatisfaction with the way Benedict has handled the sex abuse scandal, with Catholics nearly as critical of the pope as the rest of the population. Benedict's four-day visit to the U.K. has been clouded by the abuse scandal, as well as by opposition to many of his policies and widespread indifference to his presence in this deeply secular country.

Catholics are a minority in Britain at 10 percent, and up until the early 19th century, they endured harsh persecution and discrimination and were even killed for their faith. King Henry VIII broke with Rome in the 16th century after he was denied a marriage annulment.

Benedict was to meet with the Archbishop of Canterbury Rowan Williams later today amid new tensions between the Anglican and Catholic churches and celebrate an ecumenical service in Westminster Abbey.

His main event today was an afternoon speech to British politicians, businessmen and cultural leaders in Westminster Hall where he was expected to press the need for faith to help shape public policy.

In the morning, Benedict told Catholic educators at a London university their role was fundamental to forming future generations who had faith and were responsible citizens of the world. But he also reminded them they must "ensure that our schools provide a safe environment for children and young people."

"Our responsibility toward those entrusted to us for their Christian formation demands nothing less," he said. "Indeed, the life of faith can only be effectively nurtured when the prevailing atmosphere is one of respectful and affectionate trust."

Outside the university hall, some 4,000 young students, outfitted in prim school uniforms and waving small white-and-yellow Holy See flags, gathered in a field to serenade the pontiff with songs and hymns.

Benedict began his four-day U.K. state visit Thursday, greeted by Queen Elizabeth II at Holyroodhouse Palace in Edinburgh, Scotland.