The dad-of-two was asked about his kids as he opened the Royal Marsden NHS Foundation Trust's new centre for breast cancer on May 2016.
"They're both doing very well at the moment," Prince William replied when Kathryn England, 59, asked him about his kids.
"They're noisy but lovely. I'm just trying to sort out schools now, it's going very well."
George, two, is currently following in his father's footsteps by attending a Montessori nursery.
The toddler started Westacre Montessori School nursery in Norfolk, on Wednesday 6 January.
A Montessori school takes an approach to education based a child's own development, rather than expecting pupils to all reach standards at the same age.
The Duke and Duchess of Cambridge often give insights into snippets of their family life when taking part in royal engagements.
In February 2016, the Duchess revealed Prince George is "obsessed with planes".
"George is now obsessed with the air cadets and wants to join," she told Lucinda Conder, 19, who won top female cadet of 2015.
"We are going to have to push that one when he gets to 12."