Why are most top engineering schools large state schools?

Different schools may have different within-major and out-of-major elective options, even if the core curriculum for the major teaches similar principles. There can also be structural differences between how different schools teach the same material.

Some schools may have a more pre-professional emphasis, emphasizing co-ops and the such. Others may have a greater emphasis on research that can help a pre-PhD student. Of course, many schools have opportunities for both.