C.,
You can chop the rhubarb and just freeze it without boiling. YES you can use it later to make jam, it should work just fine. You might find that for bread it will be kind of mushy when it thaws. The freezing process breaks down the cellular structure of the rhubarb allowing the juice to come out. It should still work great for cobbler though.
My Mom froze rhubarb all the time when I was a kid. Here is some info I found on a website....
Preparing for Freezing:
. Wash stalks and remove all leaves. Trim and cut into 1-2 inch pieces or lengths you find suitable for freezing. Rhubarb can be frozen either raw or preheated. Heating rhubarb in boiling water for 1 minute and cooling promptly in cold water helps retain color and flavor.
Best Freezing Method(s):
Unsweetened (Plain) Pack
Pack cleaned and prepared rhubarb (either raw or preheated) tightly into suitable containers, leaving 1/2 inch of headspace. Seal, label and freeze.
Syrup Pack
Pack prepared rhubarb (either raw or preheated) tightly into containers and cover with a medium syrup (3 cups sugar to 4 cups water). Leave 1/2 inch of headspace. Seal, label and freeze.
Suitable Packaging:
Freezer containers should be moisture and vapor resistant and should not be prone to cracking or breaking at low temperatures. Containers should provide protection against absorbing flavors or odors and should be easy to label. Suitable packaging for freezing rhubarb includes freezer-grade plastic bags, rigid plastic containers or glass containers, heavy-duty aluminum foil and foil containers.
Maximum Storage Time:
10 to 12 months at 0ºF.
Thawing:
Because rhubarb is usually used for cooking, baking or making jams, the loss of texture during freezing is not important. Defrost rhubarb in the refrigerator or in the microwave according to manufacturer's specifications.
Tips & Shortcuts:
Rhubarb leaves contain a highly poisonous toxin called oxalic acid. Never cook with or eat the leaves and discard them safely away from children and pets.
Refrigerating Rhubarb:
Remove leaves from stalks and place in perforated plastic bags or wrap in plastic. Store 3 to 5 days.