The height of the table is determined by the chair seat height.  The 22" table corresponds to the chair with a 12" seat height.  Your child's feet may not touch the floor as he/ she sits, but that's not usually a problem for a small child and he/ she will be able to use the chair for several years.  I know parents and grandparents that sit at their child's table for tea parties or playtime, so children can get a lot of use out of that size.  However, some people buy the 24" table with 14" seat height chairs for a 2-year old.  My thinking is that parents of children in the higher percentile heights go for the 24" table.  If you're ordering for a 6 or 7-year old, I would suggest the larger size.

We developed the 14" seat height chairs and 24" high table for people who felt their children would get longer use from this size.