Super blocks & they all have black (tires,etc). I'd have to go with the black and white or yellow dashes down the center. This will add visual interest, & later, as he is older, reality-check & attention to detail to notice road "signs". Language is not just "alphabetic" reading, but other indicators of information(paw prints when hunting,street signs, map designations, etc.) This teaches him to observe his environment, and interpret possible information in short-hand form. This takes the quilt from cute to a learning tool. IMHO.