Grandma Lingley's sweetcorn freezing recipe:

4 qts corn (cut off raw)

1 cup sugar (optional but suggested)

4 heaping Tsp salt

1 qt water

Cut off corn and scrape cob.  Cook corn for 10 minutes after bringing to a boil.  Cool the mixture (do not drain off liquid) and scoop into freezer bags and freeze.  To eat, simply heat and add butter.

Tips: 

Don't try to cut too closely to the cob.  Do the best you can, then turn the knife sideways and then scrape the remaining corn off.

Set your pan in ice water to cool before bagging.  You can even freeze milk jugs of water beforehand to help cool your batches.  DON'T PUT HOT BAGS OF CORN INTO FREEZER.  Trust me on this...they will balloon up and maybe pop.

Lay your bags onto cookie sheets to freeze flat.  They store nicely instead of frozen globs. 

If you are doing a large volume, I have used metal grates from old refrigerators, box fans, etc to lay them on, spaced with wooden blocks.  This way no bags are laying on top of one another and they freeze quickly with air circulation around them.  Stacking a bunch of bags on top of one another creates the same problem as mentioned above, where the bags in the center don't get cold enough quickly enough and gas builds up in the bags.

I have heard of folks using electric knives and bundt cake pans to make things easier.  We still just use a shallow cookie pan and a knife.