"Slow-Children at Play" sign

Found this sign in a thrift/junk store today. Is a real road sign not a reproduction. Has rust marks on the back of the sign from where it was originally mounted on a pole and is quite heavy for it's size. I was told by the man I bought it from that it originally came from California . Think it works out well for the kids' playroom, although it could work for this "old child" too!