Early childhood educators in the United States and worldwide face the growing challenge of "schoolification,"--the imposition of conventional academic content from later grade levels into their classrooms (e.g., Ring & O'Sullivan, 2018). The science of learning offers a different approach with evidence to support more active, engaging, and inclusive educational environments for all students (e.g., Darling-Hammond et al., 2020, Hirsh-Pasek et al., 2020, Nasir et al., 2021). The Active Playful Learning framework is one promising model that combines principles of how children learn through play, and particularly adult-initiated, child-directed guided play (e.g., Weisberg et al., 2013), with the "6 Cs," a set of skills for success in the classroom and beyond. A preliminary, mixed methods evaluation of an intervention to promote guided play in kindergarten classrooms through instructional coaching was conducted by Nesbitt et al. (under review) across New Hampshire. This study builds on the prior research, first by attempting to replicate the positive effects of the intervention for teachers and students, as provided by teacher reports. It then advances beyond the previous study to determine if teacher and student behaviors shaped by guided play and the playful learning principles are detectable through independent classroom observations. Lastly, it incorporates a preliminary comparison between intervention and business as usual control classrooms. Results support a replication of the previous teacher reports. Other results are mixed, but they indicate significant behavior changes consistent with adoption of playful learning, even if not yet guided play. This study represents a considerable advance in our implementation and evaluation of Active Playful Learning for educators and students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]