During the engagement, the 37-year-old took part in a number of activities from making Christmas decorations and DIY reindeer food to posting letters to Santa.
Kate also helped the children to find Christmas trees for Family Action schools during the outing before warming up inside with a cup of hot chocolate.
Not one to miss out on an opportunity to flex her fashion know-how, the royal dressed in seasonal red and green for the big day courtesy of a puffer by Perfect Moment finished with a Really Wild knit.
Although it's not the first time she's sartorially embraced all things December, as the Duchess of Cambridge joined NATO leaders for a reception at Buckingham Palace on Tuesday evening in an emerald green Emilia Wickstead dress.
During her latest outing, the royal teased details of the way in which the Cambridge family celebrate the big day.
"She was asking about the trees which drop their needles and those that don't, and which ones smell nice!" farm owner Roger Brill revealed. "She said that they normally have the Nordmann Fir inside that doesn't drop the needles."
In fact, it seems Kate is quite the budding expert when it comes to the art of Christmas tree shopping.
"She was fantastic with the youngsters. She was in there moving them around and holding them up," Brill continued. "I will have to give her a job at the weekend, I think. She was a very good saleswoman!"
This article originally appeared on marie claire Australia.