Yep - you read that correctly - she's doing it without training wheels.
We tried it a few different times over a few weeks, at home, just on the sidewalk, and weren't sure if it was just that she couldn't get going, or couldn't steer or what. So today we finally decided to take her to a big wide-open parking lot with a slight incline, so she could get the speed going downhill and not have to steer too much. I think she even got it on the first try! Then she worked on stopping - not just by dragging her feet (and ruining her shoes :) - first coasting and then braking. She can do both well now, and can also turn around OK by making a big loop.
Then we went to Walmart and got her a big-girl helmet - as promised when she could ride her bike herself without training wheels. I also got a helmet, because I needed one (never had one, actually), and I told her when she got better at steering and stopping on demand, we'd go on bike rides together. She's working on steering - in a couple of movie clips in the parking lot you can hear "stay between/on the cracks" - that's to try to go a certain direction or straight.
Well, after she learned, all she wanted to do was continue practicing. She's very proud of herself, and I'm so proud of her too! So, when we got home, she practiced on the sidewalk again. She has a little bit of a hard time getting started, because that's when she has the hardest time steering. The sidewalk being narrower, she'd end up in the grass and get stuck. But she could do it, and went several times from one neighbor's driveway past ours and to the other neighbor's driveway, then stop and turn around.
Kaylen was bummed when it was time to come in and have dinner and go through our regular nightly routine. She's got her 2nd & final week of swimming lessons evenings this week, then VBS evenings next week, but she'll have more time to practice the next couple weekends.
P.S. Sorry Karen, it's looking like you might not be able to borrow my bike after all.