But first if you liked the child's train plan last week, here is a train whistle plan to complete the child's enjoyment of the train.
So here is a great article on the development, and methods, of frame and panel, case construction. This method of construction is pretty much the standard today, in various degrees of quality, depending on how much you want to pay. I was surprised to learn it has only been around since the end of the Renaissance period. Previous to that furniture tended to be heavy and clumsy and didn't last, due to a poor understanding of the need for proper drying of wood and construction methods that aloud the wood to breath.
When starting out many of us are still finding these things out the hard way. Early in my woodworking explorations I built a nice A frame rocking cradle for the baby room. I made the classic mistake of supporting the bottom with a batten, glued and screwed to the bottom edge of the cradle end pieces, that were not evenly dry. The bottom of one end piece unable to "breath" developed a crack extending 4" up the end piece. The top of the end piece was not restrained and could breath so the crack did not extend any higher. The cradle lived longer than the child had need for it, but that crack was always there, to remind me that wood has to be properly dried and aloud to breath.
So for a well written and illustrated article on case construction read on.