One method for freezing fresh corn without blanching it is to simply freeze the ear whole. Another method for freezing unblanched corn is to freeze just the kernels.
To freeze whole ears of corn, remove the husks and all the corn silk. Add the whole ears to freezer bags, and remove the air. Store them in the freezer.
To freeze just the kernels, shuck the corn and remove all silk. If possible, set the thick end of the corn into the hole of a Bundt pan. It's also possible to use a small bowl inside a large bowl to secure the corn. Use a small, sharp knife to remove the kernels from the cob, cutting as close to the cob as possible. Spoon the kernels into freezer bags, remove the air, and seal. Vacuum packing the bags helps the corn stay fresh longer.
If you don't have a vacuum sealer, use a straw to suck the air out before fully sealing it. Once the corn is inside the bag, push as much air as possible out, and seal the bag. Open just a enough of the zipper to slide a straw inside. Hold the opening on both sides of the straw, and suck the air out. Carefully remove the straw to prevent more air getting inside before finally sealing the bag.