I also like freezer jam because it calls for MUCH LESS sugar than traditional jam (1.5 cups with freezer jam compared to 4 or more cups with traditional jam). So, without further adieu, here's how to make freezer jam in 6 simple steps:
Step One: Gather your materials
You'll need 3-5 pounds of the fruit of your choice, 1.5 cups white sugar, one package of Instant Fruit Pectin (note: lately, I've only been seeing the packets that make 2 jars in the canning isle--make sure you get the packet that makes about 5 half pint jars, which you may have to go to the gelatin isle to find), and some freezer safe canning jars. Some glass jars are freezer safe, but not all. So, if you're in doubt, I'd pick up a few packages of the plastic freezer jam jars. Just FYI, I have always gotten more than 5 jars worth of jam, so you may want to consider buying an extra package of jars.
Step Two: Mash your fruit
Use a spoon or a potato masher to mash your fruit up, while leaving a few chunks. I know some people use a food processor, but I don't recommend it--using a food processor can break down the natural pectin in the fruit, which can prevent it from setting up like jam. Anyway, you'll need almost exactly four cups of mashed up fruit.
Step Three: Combine the sugar and pectin
Pretty self-explanatory. Stir the sugar and packet of pectin together in a large bowl.
Step Four: Add the fruit
Add the fruit to the sugar/pectin mix, and stir for three minutes. No cheating on the time!
Step Five: Ladle into jars
I got this neat little funnel for less than $2 in the canning isle, and it was money well spent. I use it all the time to help ladle jam into the jars with very little mess. Most of the plastic jam jars have a fill-to line, but just use your common sense and remember that jam expands when frozen.
Step Six: Wait
Once the jam is in the jars and the lids are screwed on tight, let it sit out on the counter according to your brand of pectin's instructions (for the Ball Instant Pectin, that's half an hour). Then pop a jar in your fridge and the rest in your freezer--it keeps about three weeks in the fridge and up to a year in the freezer.
Seriously guys, it is SO easy to make freezer jam and SO worth it. Trust me, and please give it a shot! If you do try it, I'd love to hear how it went!