Guided play, or discovery learning, is an inquiry-based teaching method where teachers are coaches who create interest-driven experiences. In this study, guided play improved preschoolers ability to learn geometric shapes -- an essential component to school readiness-- over other types of instruction.
In the study, researchers taught the properties of four geometric shapes (triangles, rectangles, pentagons, and hexagons) using discovery learning, free play, or 
didactic instructiono see which playful method facilitated learning.
Researchers chose 4- to 5-year-olds because they typically display relative knowledge of shapes and often rely heavily on visual learning. A total of 70 children received one of the three instructional conditions:
Following the instructions, each child participated in a shape-sorting task where they were instructed to place all the "real shapes" in a box and all the "fake shapes" in a trashcan. Fake shapes were broken or missing pieces (e.g., a triangle that was missing one of the corners). The researcher confirmed that the child understood the task by specifically asking whether a shape was real or fake.
After 15 minutes of shape sorting, children in the guided play group demonstrated a greater knowledge of shape features than those in the other instructional conditions. Furthermore, this improvement was still present one week later suggesting a permanence to the knowledge acquired during guided play.
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