The Scarlet Sail by Betty Cavanna

Andrea Pierce, spending her summer vacation on Cape Cod, is given a scarlet-sailed Turnabout. But she doesn't know how to manage a sail boat and, being uncertain of herself, she thinks she will never be able to learn. Then Mike, the boy who is to give her lessons, further dampens her spirits by saying that the red sail which she found so cute is actually a safety precaution . . . This is just the beginning of Andrea's conflict with Mike and with herself. But soon, through new-found determination, she takes second place in the boat race and wins the admiration of the people she loves.

Paperback, 1963

Goodreads: 3.92