I cannot believe I have visited Oahu for 20 years and not been here. WOW. This is one fantastic place. I would love to go again and again (and will on future trips!). Do not miss this on your visit.
You get there by bus number 2 from Waikiki (40 minutes). It's closed on Tuesdays and expensive ($19.95 for adults, $14.95 for 4-12 year olds). But it is worth it. We spent 6 hours and did not get to see everything. My 4-year old wanted to go again the next day. There is something for everyone. The Hawaiian Hall is simply amazing - beautifully presented, informative and extensive. So much to see and look at and the building is just superb. We didn't make it to the planetarium which is a shame. We were lucky enough to see the dinosaur exhibit which is on until 15 September and a hit with kids, animated life size robotic dinosaurs that look so real the little ones got frightened at the beginning! Beautiful gardens and grounds. Nice cafe to take a break with great sandwiches or bring a picnic and sit under the trees.
The Science Centre is simply terrific, you get to walk through a smoking volcanoe, make lava, go underground, walk through the tunnel of creation, there are animal species to look at, things to touch, climb up on, drawers to open, tunnels to explore - interesting for adults and superb for kids. I haven't seen a better museum apart from Te Papa in Wellington in NZ.
To top it off, there is a presentation of some sort just about every 30 minutes in every single building, so you could spend all day listening to Hawaii's history, make lave, watch a planetarium show etc. etc.
Great views from the grounds over Waikiki.
Met some locals with kids who go weekly!
Do not miss this!