Funnily enough, while Googling views on this subject I found a thread from here asking the same question but it was super old so... A new one. I'm updating my resume and realized my first teaching job ended over ten years ago, preceding a 4-year gap. I'm not worried about the gap, but it and the time make that first job seem somewhat on the ancient side. The general trend seems to be no older than 10-15 years unless it's really good stuff, and that job fits toward the 15 years. But in the teaching world, is it still relevant enough?