Miller and Urey Experiment: What has changed?

Hi all,
Listen, I'm new to EvC, so be easy on me, alright?
In my AP Bio class, we went through the origin of life on earth, how lightening struck chemicals on primordial earth, and how amino acids were formed and these became the first proteins and nucleic acids which eventually became the first Prokaryotic cell, etc. This theory was based on the Miller/Urey experiment, which took place in 1953. My question is, why hasn't any new data been gathered on this topic, and if it has, why is it still being taught at the high school/college level?