Jarts were a brand of lawn dart toy first sold around 1950 per some sources, or 1940s per others. You would toss them, trying to land inside a circular target. They had a weighted metal tip so they would stick upright into a lawn.
This was not a very good idea.
The metal tip was heavy and could fall with enough energy to penetrate a skull. At least three children were killed, with many thousands of injuries from mild to severe. Over 6100 in the US alone were sent to emergency rooms.
Attempts to ban the toy started around 1969. The US took them off the market in 1987, and Canada in 1988.
Similar toys are sold today, minus the deadly weapon part, with nerf or blunt tips designed to avoid penetration injuries.
Here are some actual jarts.
My brother and I did the same with my parents' old set. This was in the 90s. Some things are timeless.