What are the advantages and limitations to a 3d model of earth layers?

Advantages: It gives you a better idea on how the Earth actually looks. If you are making it, it helps you learn more about the geography of the Earth.

Disadvantages: They can be difficult to make, they can be big and bulky, if you are looking at one a classmate made, it may not be accurate. 

Hope this helps :)

Sometimes but itt depends, their is a lot if drugs on campus too so you really can't just say that