This article describes a visual approach to integrating observational data into self-evaluation and peer review of teaching, practices that can lead to adoption of evidence-based active-learning strategies in STEM. This approach was designed to be implemented for undergraduate courses across disciplines. The presentation of observational data in a timeline provides a "big-picture" view of an observed class that captures the sequencing of instructional strategies and the "ebbs and flows" of student participation--in a chronological format that coheres with how instructors often visualize a class session.