A ribbon-cutting ceremony was held Tuesday to celebrate a state-of-the-art new STEM center at Chicago's Leo High School. It is part of a partnership between the school, the Exelon Foundation, and the Cal Ripken Sr. Foundation. Leo High School, at 7901 S. Sangamon St. in Chicago's Auburn Gresham neighborhood, is the first high school in the U.S. to be granted a STEM center through the partnership.