There are several ways to feeze fresh cherries but the simplest is to wash, drain and then pack them with stems intact in freezer containers. Shake the containers to pack the fruit closely, then cover tightly and freeze.
For a syrup pack, boil 1 cup sugar with 2 cups water until sugar dissolves. Refrigerate syrup until thoroughly chilled
You'll need about 1/2 to 2/3 cup syrup and 1/4 cup ascorbic acid for each pint container.
Pour 1/2 cup syrup into each pint and then fill with pitted cherries. Shake container without crushing. Finish filling container with cherries, leaving 1/2 inch headspace for pints, an inch for quarts.
Crumble small pieces of aluminum foil or plastic wrap and put on top of fruit. Press down to hold cherries under the syrup, then cover tightly and freeze.