I have fond memories of paint by number kits from when I was growing up. The images were usually landscapes and used lots of different colors. The paints were actually pretty smelly but that just made the kits seem less like toys and more like real art supplies.
The first paint by number kits were sold by Palmer Paint in 1951 under their Craft Master brand. This was just 1 of the many fads of the 1950’s and the kits are less popular now but still fairly easy to find.