Chop the peaches into large chunks, discarding the pits.
Place the peaches, sugar, and lemon juice in a small or medium saucepan.
Bring the fruit to a boil over medium high heat. Reduce heat to medium and simmer to thicken, approximately 15 minutes.
Use a potato masher or fork to mash the fruit as much or little as desired.
The jam is done when it is thick and more of a clump when put on a cold spoon or cold plate and tilted. If it runs like honey, it is not thick enough yet and you need to heat it longer. You want the jam to move slowly when tilted.
Store in a jar in the refrigerator for up to three weeks. Or freeze.
Follow proper canning procedures to store at room temperature. You can also freeze this jam.The volume you get will vary with how long you cook it (how thick it is) and how much you mash it.This will roughly fill one pint sized mason jar, which is perfect for storing in the refrigerator.