This was a kit sold for children 12 and up, which let them create metal soldiers and other figures. The kit included a crucible, a heating unit, and lead ingots that you would melt in the crucible, to then pour the molten lead into molds.
I assume you could then paint the resulting figures, if you wanted.
Here is a photo showing those components. The crucible and electric heater are on the right. I suppose(?) you would file or trim away the flashing and pour-funnel from the final cast figure, but this photo shows the result straight out of the molds.
Ages 12 and up.
I would bet the difference is mainly between who chewed on their toys versus not, who washed their hands before eating with their hands versus not