These were usually records that were put out for children by the big labels. In the early 50s they came out in both 45 and 78 form. RCA had the "Little Nipper" Series. Decca had the "Children's Series" and Capitol had the "Bozo Approved" series and the "Record Reader" series where you followed along in a booklet attached between the covers, and read along while the record played. RCA also had versions of this.