Wash the squash well under running water, trim off the ends, and cut into rounds, chunks, or dices.
Fill a large pot with 1 gallon of water, place on the stove, and bring to a boil over high heat. While the pot is heating up, fill a large bowl with the remaining water and ice cubes.
Once the water comes to a boil, drop the prepared zucchini and summer squash pieces into the boiling water, and boil for 1 to 3-minutes.
Remove the squash and plunge into the bowl of ice water to cool for about 5 to 10 minutes.
Once the pieces have cooled, drain, and air-dry on a clean kitchen towel.
Pre-freeze the squash by laying the slices in a single layer on a parchment lined baking sheet, and freezing until solid.
Add the frozen zucchini and summer squash to freezer bags, remove air by sucking out with a straw, and seal the bag. Label and date and store in the freezer until you are ready to use. Use within 8-10 months for the best quality and flavor.