If you've never been to Oahu, I would recommend this tour. I would add a Pearl Harbor trip as well. We booked this trip through the Pearl Harbor website which you could add this tour to it as well.
My wife and I had done this tour 24 years ago the first time we visited and took our teenagers, 15 and 18, with us this time. Our son, 18, loves history, so Pearl Harbor was his favorite. My 15 year old daughter didn't care for much of this tour besides a shopping spot and some of the beaches. The tour we took was about 6 hours which included lunch.
There were a few stops we didn't get to make that were listed. One was Hanauma Bay, which I would recommend a visit, because we took our tour on a Tuesday, which is the one day of the week when they are closed. We skipped a couple of other spots because of the rain that day. We still had a pretty full day though.
Dole pineapple plantation is kinda neat. Pineapples for purchase there are extremely good. We got the pineapple soft serve there which is amazing. The amount of time you are allowed there doesn't give you a lot of time to do some things. There is a pineapple maze, which takes about an hour to do and the pineapple express little train they have that takes you through the grounds.
Halona blowhole is a beautiful spot as well. We also stopped at a macadamia nut farm where you can try samples and purchase your own; just as you can do at the Dole pineapple plantation. We stopped at Pounder's restaurant for lunch. Not sure if the tour company gets anything from the places we stopped for bringing their tours there, but we enjoyed everywhere we stopped. Most stops we were able to shop for souvenirs or buy some local food for snacks along the way.
Some of the tours say don't bring a bag. We ended up bringing one and were told we could leave it on the bus. You can't bring bags into Pearl Harbor, they do have a place to store your bag for $5, but if there is a line, you may not want to mess with that.
Waimea Falls, Waimea Bay and Sunset beach. Clumping all of these in one group since they are so close in proximity to each other. Waimea Falls is in Waimea Valley which is a botanical garden. The Falls are about a 15 minute walk from the entrance on a paved walking path like at a zoo or something. The botanical gardens are beautiful. Plants and flowers are everywhere. If you love taking pictures of things like that, the walk to the falls will obviously take a bit longer. The falls are very pretty as well. If you have the opportunity to swim in them, I would recommend it. They provide life jackets as they are required to swim. The water was pretty chilly, but feels great on a hot day. They do have lockers to rent and a restroom nearby. You could also pay to ride a golf cart from the entrance to the falls and back. I think it was about $10 a person roundtrip or $15 one way. I didn't think it was worth it, so we walked. Waimea Bay is spectacular. We went there on our own on a different day and spent the evening there until after sunset. There is a cliff you can climb up and jump off of as well that is about 25-30 feet. There are lifeguards there as well.
Again, if you've never been to Oahu, this tour helps you get a broad view of what there is to see and do. I definitely would recommend it. Teens need to just keep an open mind and enjoy the views and experiences.