We visited during 1/2 term last week, my 2 children (9 & 7) and my mum.
We paid £5 to just go into the park with the car. We'd actually decided to go to visit to working farm, so we walked down from the car park to the farm, not far, but no price list at the start of the drive to the park so when we got there It was £14.80 for us to go in on a family ticket, although I think you could take up to 3 children in on that ticket. We aren't national trust members but I believe they got a discount to go into the farm.
There was an exceptionally helpful man who worked for the farm (I think his name was Al??) , he took the time to explain all about the shire horses and got out Blossom for the children to groom.
Unfortunately that's where the good points end. There were a few goats to feed, a code of cows and chickens walking around but that was it. Didn't see any pigs, or rare breeds etc. no demonstrations or anything to help with ie feeding etc. there was an adventure playground, but more like an obstacle course, not much fun for older children. Overall we thought it was very overpriced. We'd looked round everything in about 20 minutes. There was a playbarn, but only suitable for toddlers.
We then walked back up to the main part of Tatton to find that the mansion was closed until the end of March, but if it had been open that was an another £14.80!
We had lunch in the restaurant in the courtyard area. The choice and quality of the food was good, but it was heaving with customers and they didn't have enough staff on to cope. Quite expensive for main courses for what you had but nice enough.
The children then found the adventure playground, which was free and very good. I was very cold the day we visited but I'd imagine on a nice day in summer they'd have been happy playing there for a long time.
Overall, we felt it was overpriced for what we did, but we would love to visiting againk in summer. Take the bikes and a picnic this time and I'm sure it would be a nice day out.
I also noticed that you can take horses into the park for £4, our darters would love to take their pony so maybe that would be nice too.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.