We stayed at Schooner Landing, which is ideally situated for viewing tidepools and ocean life. A short walk down the stairs, and you're there. All types of sealife are visible at low tide, like mussel beds, starfish, anenomes, sea snails,crabs and other critters. The kids were able to get an up-close view without going to an aquarium and it provided great conversations to discuss nature and biology with the kids. We even took some photos of the kids standing next to rocks with large starfish next to them. This was probably one of their favorite parts of the trip was seeing the "middle zone" at low tide.
Even if you have to get up at 6am to get to the beach during the minus tide, it is worth it because you can't see as much if you do wait. I recommend to get to the beach 1 hour before the low tide so that you can fully enjoy the sealife. From the beach, you have a fabulous view of one of the many Oregon Lighthouses. The kids had never seen one up-close. You can also beachcomb for agates, shells, and sand dollars. It is the perfect place for the family.