The Pope spent the second day of his visit to the UK in London.
In the morning, around 4,000 school kids came to a huge gathering called The Big Assembly and the Pope spoke to the crowds.
After weeks of preparation, lots of children got the chance to perform in front of the Pope.
Andy Akinwolere from Blue Peter was also speaking at The Big Assembly.
Pope Benedict XVI arrived in Edinburgh on Thursday morning to start his four-day visit to the UK. It's the first time a Pope has visited Britain since 1982.
It was a rather windy morning on the airport tarmac!
The Pope was greeted by Prince Philip and a 30-strong guard of honour from the Royal Regiment of Scotland.
Security is really tight for the Pope's visit - there are hundreds of police officers on the streets of Edinburgh to make sure the visit goes smoothly.
There are millions of Catholics in the UK and thousands of people are lining the streets of Edinburgh to greet him.
The Pope was officially welcomed by the Queen and Prince Philip at the Palace of Holyroodhouse in Edinburgh, where the Queen lives when she's in Scotland.
The Queen and Pope Benedict XVI also exchanged gifts. The Pope received a special book of 16th century drawings and the Queen was given a copy of the Lorsch Gospels.
He's travelling in a specially converted car called the Popemobile. It's armour-plated and has bulletproof glass.
And it's got a special seat for the Pope so that everyone can see him as he parades through the streets of Edinburgh.
Thousands of people have gathered in Bellahouston Park in Glasgow hoping to catch a glimpse of the Pope before he celebrates Mass on Thursday afternoon.
There a millions of Catholics in the UK - and it looks like some of the Pope's followers are pretty young!
Singer Susan Boyle took to the stage in Bellahouston Park to entertain the crowds.