Combine the sugar and smashed strawberries (see note) in a large bowl and allow to sit for 10 minutes.
Place a medium saucepan over medium heat. Add the water and pectin to the pan and whisk together. Bring to a boil, stirring constantly. Allow the pectin mixture to simmer for 2-3 minutes.
Pour the pectin over the strawberry mixture. Stir and let sit for 2 minutes.
Pour the jam mixture into six 8-ounce freezer-safe mason jars. Be sure to leave about 1/2-inch of space at the top.
Let the jars rest on the counter for 24 hours. Then, store them in the freezer.
Allow the jam to thaw in the refrigerator overnight before using.
Notes
Freezer jam can be kept in the freezer for up to 1 year. Once thawed, it'll last up to 3 weeks in the fridge.