Conversation so far:
What was Isaac Asimov's first job
Isaac Asimov spent three years during World War II working as a civilian chemist at the Philadelphia Navy Yard's Naval Air Experimental Station.
What was Isaac Asimov age of starting school?
Isaac Asimov attended New York City public schools from age 5.
What school didIsaac Asimov attend?
Boys High School in Brooklyn

Question: What age did he graduate
Self-contained rewrite: What age did Isaac Asimov graduate high school