This is one part activity, one part party food. Kids will enjoy the pulling, cutting and shaping of the taffy. Guests can save their candies in waxed paper and take them home for their families.
Combine sugar, water, vinegar and butter in a heavy, nonreactive pan, and stir over low heat until the sugar dissolves.
Raise heat and cook quickly, about 20 minutes, without stirring, until a teaspoon of the mixture dropped into a glass of cold water forms a hard ball.
Watch the boil carefully so the taffy does not burn. Turn off heat and add the vanilla extract.
Pour the taffy onto a generously buttered platter or cookie sheet with low sides. When it is cool enough to handle (adults do everything up to this part), kids grease their hands with butter, take a lump of taffy, and pull and stretch it until it is light and slightly firm.
The more they stretch, pull and twist the candy, the more air they will blend into it, and the more like beach taffy it will get.
Using scissors, cut the lump of candy into bite-size pieces. When completely cool, wrap each piece in waxed paper. Makes 45 1-inch candies.