Big Island Hawaii. what is cannot miss to see

Green Sand beach on the south side of the island
Love Hapuna Beach
Also enjoy Waipio Valley
You can jump off 6 ton bridge just north of Hilo
I love ocean sushi deli in Hilo... but I was a college kid so who knows if it is good

Lived there for my junior and senior years

I'll be there at end of July for the first time also. We are staying just north of Hilo in vrbo house overlooking the ocean for 3 nights them the fairmont on the west side for 5.

We booked a helicopter tour of volcano and waterfalls through Paradise Helicopters. We will do Waipio - probably the atv tour. Also, volcanoes national park and some hiking while on that side.

As for the other 5 nights, some sunset dinners, manta ray night swim, several beaches, and I'd like to visit Mauna Kea one night for stargazing at maybe the best place on the planet for doing so.

Of course we rented a Jeep for the week.

Donkeys apparently. Seriously though, we just missed the crazy lava flow happening now. We did the volcano and waterfall helicopter tour out of Hilo, but I heard the boat tour is good too. Not sure what the situation is like now, but worth doing at least one of them. Akaka Falls is on the drive to Hilo, which has a paved path overlooking the falls.
There are a few breweries you can hit like Kona and Big Island.
We were supposed to do the Mauna Kea Summit Adventure Tour, but there was too much snow. Wish we could've done it.
Green Sand Beach: bring tennis shoes if you're walking to it. If you're paying the locals to run you down there, prepare for a bumpy ride. Going early in the day is best, less crowds and cooler.
The best white sand beach we hit, Manini'owali Beach, is across the road from the veterans cemetery just north of the airport.