My 8 year old son got a kayak for Christmas and we went to Riverside Park to try it out. They have a small dock on a pond near the park building that my husband and I used to put in our canoe and two kayaks. We let my son practice in the pond which lead out to the canal. When he had himself together, we paddled up the canal.
It isn't terribly exciting and technically you are going up stream, but it doesn't feel like it. There are some remains of bulkheads and a moss and fern covered rock wall to look at, so not anything you would do any serious paddling on, but for a child learning to kayak, it was calm, easy, and sheltered from the wind. I also think it is pretty shallow.
We saw a small beaver lodge along the way and now and then a bird. It fit the bill for what we wanted which was an interesting, controlled environment to let the kids have some fun.
There is a park office and restrooms (which were locked on the weekend). There are picnic shelters, a river map, and trails along the canal and down to the Appomattox river.
The Park is located at 21514 Chesterfield Avenue, Ettrick, VA. This is also a take out point from the Appomattox Canoe Launch at the Chesdin dam.