Sentence:  In all placs and ages children have played with things, some found by children, some fabricated by them, and some provided by parents or other adults. Today these might include a just-emptied rolled-oats carton salvaged from the kitchen, a knocked together wooden <WSD>wagon</WSD> set on cast-off baby buggy wheels, or a gaudy heavy plastic gm set of Chinese manufacture. 
Meaning of the word marked with <WSD> tags:  A four-wheeled child's riding toy, pulled or steered by a long handle attached to the front.