I'm doing a school project on objects that change temperatures the fastest. I'm trying to test metal, glass, plastic and rubber. Can somebody out there help me with this?

Don't know of fastest. I Know Aluminum cools fast and heat fast. It is used as heat sinks to dissapate heat. Whatever is faster would have to be more expensive than aluminum.
Here I am Talking about Metal.

I would have to guess plastic because obviously it would be affected faster by an open flame, over the other listed materials

I'm not entirely sure what you're asking, but metal has the highest thermal conductivity due to the free electrons which can travel through the metal moving the heat around.

I'm not sure I follow your logic hvacm you mean that maybe plastic would mealt faster? That would actually make it change temprature slower - Objects don't change temperature when they're at their melting point.

Changing temperature seems question, Heating or cooling. Since Burning snd melting
Are destructive, Beyond heating and cooling.
If a 2" cube of metal, glass, plastic, and rubber, were brought up to temperature,
Just short of melting or burning. What would you be able to touch first?

Why not just read your book or do the experiment?

But unfortunately as many have said above, it's metal.