Wash and dry the ripe peaches, slice in half, remove pits, and chop into bite-sized pieces, leaving the skin on.

In a large pot, combine chopped peaches, sugar, and lemon juice. Stir until sugar begins to dissolve, then let it sit for 30 minutes.

Place the pot over medium heat and bring the mixture to a gentle boil, stirring frequently for about 5-10 minutes.

Reduce heat and simmer for 20-30 minutes, stirring occasionally, until the mixture thickens.

Preheat your oven to 200°F (93°C) and place clean, empty jars on a baking sheet to sterilize for 10 minutes.

Ladle hot peach jam into sterilized jars, leaving 1/4-inch headspace at the top.

Wipe the rims of jars, seal with lids, and allow to cool at room temperature until you hear a 'pop' sound.