The purpose of this study was to identify if and how STEM (Science, Technology, Engineering, Math) lessons help student progress toward achieving benchmarks in AASL (American Association of School Librarians) 21st Century Learner Standards. This study was conducted in the library media center with 48 kindergarten students participating. The researcher taught mini-lessons for the AASL Standards prior to students participating in the STEM activities. The data were collected on 23 benchmarks included in the AASL Standards. Students were rated on these Standards as beginning, progressing, or achieving. Data analysis indicated that the STEM lessons were an effective means for providing the students with developmentally appropriate ways to make progress toward the AASL Standards. Data analysis also revealed that the STEM lessons were effective in reducing the number of students rated as beginning, as well as pushing some students into the achieving category.