Many libraries are now providing innovative science, technology, engineering, and math (STEM) activities in their youth programs, including interactive exhibitions and hands-on workshops. What started some years ago as independent experiments has become a national movement. More and more libraries are responding to the need to increase science literacy and support 21st Century skills, such as critical thinking, by adding to STEM programs for patrons of all ages, from pre-school to adults. With the introduction of STEM into the library’s traditional programming, librarians need to evaluate the