Hot Wheels!
Kept my friends and I busy for hours a day.
I remember the first year Hot Wheels and the track came out. They couldn’t keep up with demand. The cars were $1.00. You really took care of the cars to avoid scratching the paint. Some kids oiled the wheels which tended to crack the wheels. It was like Pinewood Derby. Some cars ran better on some track configurations than others. Always enjoyed testing them and thinking about owning real one when I got older.
Sometime later they encouraged kids to crash them into one another. I never understood that.