This toy is a simple spring-based marble or Hot Wheels car shooter.
Designed for young children, the operation of this toy is quite basic,
just pull back the plunger and let it rip.
Key features include:
Simple spring mechanism that teaches kids about potential energy
and Newton's Third Law (action/reaction pairs)
Clear plastic casing to allow curious minds to view the spring
mechanism
Hot Wheels track attachment for endless ramp, jump, and course
possibilities
Thoughts on construction:
The case would be made out of a strong but clear plastic, most
likely plexiglass or clear acrylic
The plunger could be made of 1/2" cast or extruded acrylic with
a small handle/knob fused on the end and the pusher screwed on to
the other end
In terms of durability, there is little that can break. Poor fusion
of joints would result in an overall weakness, but that can be avoided
with good manufacturing practices
As there are few moving parts, this toy is relatively safe. If
taken apart, the pusher and plunger can become safety hazards. The
spring can be dangerous, but this danger is minimized by placing
a cover over the spring at the point where it is most compressed,
thus stopping possible pinching hazards