Looks like a CWC with a lazy heart chain ring sprocket (24-tooth girls). The seat post clamp looks like a later CWC design, (with the bulge in the middle). The fastener holes in the head tube look like they would accommodate a 2+7/8” CWC head badge. Almost looks like an early frame because the rear forks (or chain stays) are straight and not the curved design (for full size bikes), but even later AMF may have reverted back to the straight tubes. Another tell is the U-shape (or J?) sheet metal (versus round tube) for the seat stay bridge. With the rear drop outs, likely the frame is early post war ~1947-C or so, the serial numbers may yield the date.
What size are the tires/wheels — 24”?
Front fender may be backwards(?).