Here are the first sweet potatoes we dug up last week - these were just the ones that I could see poking up above the soil. That one on the right, nearest the phone is almost 2 pounds!
Here's another picture of all of them (sorry its on its side, I'm not going back to fix it now). The one on the upper right is the same big one as above.
I estimate that all these, plus the 2 we've already eaten, the 2 more my mom found a few days later when she used the shovel to dig up the whole area and the couple I left at her house - all told I think we got about 12 pounds of sweet potatoes. I could tell that we got more sweet potatoes from the areas where we had amended the soil better. There were a few plants at the back or right at the edge of the garden that didn't produce as well. Guess we know what we need to do better next year!