This was my first time making jam. It was so easy to make and tastes great!!! My 9 year old son loves it. (I didn't even know where to get the jars from because it is not "the season" to make jam in MD yet! The craft store had the jars in stock.) Here are a few tips and/or lessons I learned... 1. Use a blender or chopper and puree the strawberries until you have four cups. 2. I did not have a thermumeter, so I brought the mixture to a rolling boil stirring consistency for ten minutes. (All you will see is bubbles all over the bottom of the pot and foam in some areas. If you put a lid on, it will boil over your pot.) 3. I did the cold plate test to see if the mixture would jell. The first time I was unsure, so I gave it five more minutes of rolling boil time, then tried the plate test again. 4. When you get the jars ready, after soaking them in hot water, use tongs and silicone mitts to handle the glass jars because they will be VERY hot. 5. Place the strawberry jam mixture in the hot jars and put the lid on right away and then turn it upside down. 6. I waited 5 minutes and then turned them back over. This seals the jars. 7. Your jam will not look like jam/jelly, more like thick syrup. 8. Wait for it to "set" After 48 hours you will know if you did it right. 9. I got 2 and a half 16oz jars out of this recipe. I hope this helps. Check out the mason jar pics of my finished jam. Enjoy and Good Luck!