Do some Google searching on the items I list, and see if they interest you.
I lived there for 11 years. Always liked Sea Life Park. The Polynesian Cultural center is a good educational event. Pearl Harbor is a must, if you are the least patriotic, and a cheap ride.
Ala Moana shopping center was the largest in the USA at one point, maybe the world. If you like to shop, there is always the international market place.
Plenty of beaches to see. If you want to see big waves, go to Sunset Beach.
There is the Pali Lookout, which is very historical. It will be windy and cold.
Rent a car. Go on a island tour, it's only ~60 miles. Stop at every scenic point and make a day of it.