Bryan Cranston certainly puts the "meth" in method actor ... 'cause back when he was a teenager, the "Breaking Bad" star was a member of his high school chemistry club, TMZ has learned.
40 years before he was Walter White, Cranston was just a regular science nerd from the Valley ... who joined the Chemistry Club at Canoga Park High School in L.A. back in 1973.
Fast forward a few decades ... and Cranston has become a TV legend playing the most famous meth-cooking chemistry teacher in the country. Funny how life works.
Besides the science thing ... Cranston was also a staffer for the school's weekly newspaper ... where he rocked a shirt that looked like he was ready for Studio 54 -- where the coke was 99% pure.