Our family of 5 booked the 12:30 half day kayaking trip. Luckily nobody else was signed up for that time! Our guide was nice and kept us safe, although we thought she could have had a bit more personality.
We saw seals popping their heads out of the water, green crabs, a red jellyfish and a lobster boat. We were given a choice of single or double kayaks. Our 12 year-old daughter insisted on a single and, though she's decently strong and has some kayaking experience, she held us back. If we had it to do over we'd take a double kayak and make sure she was in it with someone else.
They say that if you go in the morning there's a greater chance of fog, but in the afternoon the winds can kick up. We got lucky and had nice weather.