In a large saucepan, measure the exact amount of sugar. Do not use less sugar, it will not work. Stir in a packet of less sugar Sure-Jell and water. Bring this mixture to a boil over medium heat, stirring constantly.
Boil the sugar, Sure-Jell, water mixture for 1 minute, stiring the entire time. After one minute, remove from heat.
Crush strawberries in a large bowl with a potato masher. Use two bowls, one to crush the berries and one to measure out the exact amount. A dry measuring cup is the easiest way to measure the crushed strawberries.
Add the Sure-Jell mixture to the crushed strawberries. Stir for 1 minute.
Fill the jars or containers right away. Using a wide mouth funnel makes this task less messy. Leave ½ inch space from the top. This will give the jam enough room to expand when it freezes.
Let the jars stand at room temperature for 24 hours. Refrigerate up to 3 weeks or freeze for 1 year. Defrost before using.
Notes
Note 1: Do not swap out a different type of sugar or use less. The jam may not set.Note 2: Use the Less Sugar Sure-Jell in the pink box. This is what the recipe was tested with and had great results. Storage: Freezer Jam must be stored in the refrigerator for up to 3 weeks or in the freezer for up to 1 year. It is not shelf-stable.