The power of 3D printing technology has grown exponentially in just the past few years--people around the world are using 3D printers to prepare food, create tailored clothing, build cars and homes, and advance the medical field in ways that never seemed possible. In classrooms across the nation, 3D printers have become increasingly common because of their affordability and ease of use. Given the focus the "Next Generation Science Standards" (NGSS Lead States 2013) and the "Standards for Technology Literacy" (ITEA 2007) place on engineering and design, 3D printers are enabling students to create tangible design solutions and inspire models of applied science, technology, engineering, arts, and mathematics (STEAM). Teachers have recently begun to capitalize on the benefits of using 3D printers to facilitate makerspaces--spaces where people can gather to create something or learn how to--in elementary classrooms. Allowing young students to create and innovate their own design solutions to real-world problems emulates how real science and engineering is done. In this article, the authors explore how one teacher employed 3D printing technology with fourth-grade students in a Science, Technology, Engineering, the Arts and Mathematics (STEAM) lab to design and create a prosthetic hand. Mr. Smith's (pseudonym) vision for the STEAM lab, which he conceptualizes as a makerspace where learners of all abilities use multiple disciplines to solve problems, is to inspire a love of learning in students and to create a space for authentic inquiry about their world.