The geoscience workforce, particularly in ocean sciences, lacks diversity. Implementing culturally responsive teaching and mentoring practices throughout the K–university pipeline is one way to help increase diversity in the field. Here, we describe initial results and lessons learned from a pilot course conducted through a partnership between the University of California San Diego (UCSD) and the Ocean Discovery Institute (ODI), a local nonprofit that provides opportunities for low-income K–12 youths to learn about oceanography. The goals of the pilot course are to educate a racially diverse group of UCSD undergraduates in culturally sensitive mentoring practices and provide opportunities for them to apply their newly acquired skills while working with K–12 students at ODI. The undergraduates prepared and implemented lessons designed to demystify the college experience for their mentees. Through classroom experience and weekly journal reflections, undergraduates developed confidence and improved their ability to mentor youth.