Adrian Brown, 47, landed in Bassingbourn Community primary school's field after a change in wind direction blew him off course.
Brown's 12 and 15-year-old daughters, who study at a nearby secondary school, watched him land.
The dad said he planned the landing to avoid a dual carriageway and sheep in neighbouring fields.
"I could see there was plenty of space to land safely on the school field so I decided to pull in there," he said. "As I came down the headteacher came up to me and said, 'This is so exciting!'."
Brown, an engineer from Litlington, Cambridgeshire, has been hot air ballooning for 25 years and regularly flies his one seat Cloud Hopper balloon when conditions allow him to.
He said the wind direction changed as soon as he took off, so he knew he wasn't going to be able to land where he had originally planned.
He chose the school playing field because it was not only a great location to get to see his kids, but it was also close to the road and clear of farm animals.
"There was a bit more of a crowd than my normal landings," said Brown. "My daughter came across and said hello, which was lovely."
Charlotte Perkins, 45, who captured the landing on video, was dropping her two children off at school when the balloon made its entrance.
"We saw the balloon on the walk to school and couldn't believe it when it pulled into the field," she said. "The children loved it."
By happy coincidence, the Year 3 and 4 pupils at the primary school are currently studying 'Around the World in 80 Days' featuring Phileas Fogg in a hot air balloon.
Special education needs coordinator Vicky Tyas, 34, said: "The children thought it was planned because of their learning - but we were just as surprised as they were.
"Our headteacher, Mrs Brown, went out to see if the pilot was alright. He was very apologetic, but everyone enjoyed the spectacle.
"It was a special touch to an otherwise dull Tuesday morning. It started the day off really nicely and gave everyone a bit of a treat."
Although Brown had not originally planned to land the balloon at the school, he wanted to stress that when he landed, it wasn't an accident.
"There are accidents that happen around the world and it's easy to tar us with the same brush, but this was a planned landing," he said.
"Would I land there again? Definitely. Would I want any of the publicity? No."