We are family of 4 with two kids aged 11 and 9.
Summary - Taupo is definitely worth doing. Lots to do and you can make it relaxing easy going stuff like we did or more adventurous stuff. We did 3 full days, but easily could have done 1 or 2 more. Some good cafes if you stay away from the main tourist drag of kfc, McDonalds etc.
Day 1 - Arrive Auckland and take rental to Taupo, stopping at Hamilton for dinner (Mexican, good). Staying at Sacred Waters.
2 - DeBretts thermal pool. This is a good way to spend 1-2 hours. 2 enjoyable large hot pools, a couple smaller cooler ones and 3 water slides for the kids (and adults too if you weigh under 90kg, though one wasn’t working). Very enjoyable even if you aren’t a swimmer. After went for lunch in town at Cozy Corner (good). Then wandered through the town, popping into a couple of shops. Got gelato at Lunas (my kids loved it though I think all gelato is the same). Walked along the lake side eating then back to the hotel. Dinner at Lonetsar (average).
3 - Rapids jet boat. My kids absolutely loved it and wanted to do it again immediately. Definitely recommend. After stopped at Huka Honey- very good as get lots of unusual honey tastings plus honey wine. Sat and had a honey drink while kids played “Bee simulator” video game. Next stopped at Huka Falls just for view, no trek. It’s not a waterfall really. Just a large violent rapid. Good for a quick visit. One more stop at the bungee jump just to see someone do it up close. We were too chicken ourselves! Back to town for lunch at Victoria’s cafe (good), then back to hotel. Walked out to the lake and put our feet in to feel the warm parts. Back to hotel for thermal hot tub (just a glorified giant bath really). Dinner at Mavericks, a surprisingly good family restaurant, good steaks and pasta (much better than Lonestar). Next to Mavericks is also mini golf, ten pin bowling and VR if that’s your thing.
4 - Hired bikes from the hotel and rode along the Lion Walk by the lake. This was very easy going. Went about half an hour and got to the playground near the south end before turning back. Lunch in town. Then friends took us on their boat on the lake. Saw the Māori carvings and even jumped into the water (freezing!). Took us around the lake for a bit. Definitely recommend a day on the lake whether you do one of the cruises (conventional cruise boat or the sailing boat), or something more adventurous like kayaking, parasailing or jet ski, or even just hire a doughnut boat and steer yourself for a couple of hours. Dinner we got some takeaway and stayed in the hotel.
5 - Depart.