Prepare the jars: Bring a large pot of water to boil, and add the jars and lids. Keep in boiling water while making the jam.
Combine the fruit and sugar in a large pot over medium-high heat. Stir occasionally, until the sugar begins to dissolve, about 5 minutes. After all of the berries have cooked down some, but before it's boiling, use a potato masher to smash the berries a bit. Make sure there are chunks of fruit in the jam, but not very large ones. Bring fruit and sugar to full rolling boil, about 5 more minutes.
Stir in the pectin; bring back to full rolling boil for 1 minute. Pieces of fruit should still be visible.
Fill the jars with the jam, and seal. Flip the jars upside down on a cooling rack on the counter for approximately 5 to 8 minutes. Then flip them right-side up. You should hear a popping noise, signaling that the jars have sealed properly. Discard any that do not properly seal.