We took 4 year old DD in August for the first time. We travelled up and stayed overnight.
Day 1 we went to the Natural History Museum. She’s dinosaur and animal mad so loved it! It was unbearably hot in there, but don’t think you’ll have the same issue in November!!
After than we went to South Bank for the evening, had some dinner, wandered, went in the carousel, looked at London eye, Big Ben etc from there.
Day 2 we did a Thames boat trip down to Tower of London. Didn’t have time to do that justice so just wandered around the outside (but think we’d do it another time!?) and went on Tower Bridge.
Went for lunch in China Town then visited Hamleys; hubby has fond memories of being taken there as a kid and lots of toys, but found it a bit packed myself.
Time to head home after that.
DD loved it and keeps asking when we’re going back to London 🙂