This qualitative action research study examines how middle and high school STEM teachers create and implement lessons that connect concepts to the real-world and develop student metacognition. The researcher collected data through interviews, focus groups, document analysis, and survey questions. Participants from vocational, private, and traditional public schools are all represented. The data indicate that teachers use a variety of lesson planning tools including the Next Generation Science Standards to create lesson plans. Lessons that connect class content to students' personal experiences or current events were reported to increase student engagement and lead to deeper learning. Deep learning is defined as the formation and development of higher order thinking skills like critical thinking. The literature demonstrates that critical thinking can be developed through reflective writing exercises. According to the findings of this study, there are four different ways that reflection can be incorporated into STEM classrooms: connections to class content, connections to the real-world, connections to students' personal experiences, and metacognitive skill development. Personalized coaching can be an effective method of professional development for promoting student reflection in STEM classrooms and providing guidance for teachers to be reflective positively impacts their future lesson planning. An additional finding shows that students appreciate the opportunity to reflect on their learning periodically in order to improve their academic habits. One limitation of this study is that participants volunteered to join after viewing a recruitment poster about reflection, therefore only attracting a population of teachers who were interested in developing their students' reflective skills. Future research studies might examine a larger and more randomized sample to make broader conclusions and impact a wider population of STEM teachers. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]