A special effort to teach Newton elementary students the basic principle of how a computer works was recently completed by members of the Newton Public Library. Library Director Nicole Terry says the library received a STEM Scale-Up grant from the Governor’s STEM Council. Youth Services Librarian Phyllis Peter and Elementary Librarian Abigail Morgan visited each 3rd and 4th grade classroom three times this past fall and winter. They worked with students on a marble-powered computer that introduced basic coding. During each visit, the 3rd and 4th graders were given harder puzzles to solve, and they learned how signals are sent via switches.