One of the most impactful and transformative practices early childhood teachers can engage in is the practice of inquiry. Inquiry requires educators to be both fully present and fully engaged in professional practice while adopting the mindset that the cycle of inquiry is never complete. In inquiry-based learning, the learner is at the center of the learning process. Discovery of new learning is encouraged through questioning, observing, exploration, and the sharing of ideas and reflection. The use of an inquiry approach is especially suited to Science, Technology, Engineering, and Mathematics or STEM topics in early childhood. Capturing their natural curiosity, STEM inquiry lessons can be collaborative, data-driven, and reflective for young children, allowing teachers to promote learning for diverse groups of young children as well as improve their professional practice. Whatever the STEM topic, presenting an inquiry experience to children, while at the same time teachers use inquiry tools for planning and modifying the learning experience as it unfolds, has the potential to result in a positive learning experience for all.