The [Environmental Protection Agency] has set a 10-year deadline for most utilities to replace lead service lines, but omitted requirements for schools to replace the water fountains or plumbing that have lead components.
Archived at https://ghostarchive.org/archive/F5qXx
You just have to keep exposing them to it to help build their tolerance. Eventually, they won’t even get hurt when you hit them with a lead pipe.
Thats why I shoot kids with small caliber bullets. Just tagging them in the legs and arms with some .22 short rounds until they can build up a tolerance to fast lead.