After peeling the lemons, either juice the meat with an electric juicer or place in a blender and then strain the juice.
Add in Splenda, stir well.
Add in cold water.
Pour into 1/2 cup serving dishes or cups.
(Foods containing Splenda seem to freeze harder than naturally sweetened foods. If you don't want it to freeze super hard, add 1/2 teaspoons of salt to the ice cold water before mixing in with the lemon juice).