After I hosed them off and let them dry in the sun, I primed them with some basic white paint. I could have taken it a step further and applied something a bit "stronger" to seal or otherwise contain the grittiness, but the kids were eager to get to painting.
And then, my role in the process was over.
They sketched their ideas with pencil and painted away! I used a roll of duct tape to provide a "base" so to keep the pointier side down for that orientation.
Now to find some rope and hang them on the wall and forever remember a fun vacation on the shores of New England.
What finds do you make your own? Do share!