S.M.A.R.T.S. and the invisible robot

Fifth-graders Zoe, Jaden, and Caleb are excited about the Art of Science exhibition, featuring artwork made through scientific methods, by students at the local high school, so when the centerpiece necklace disappears from the locked gallery, the three members of the S.M.A.R.T.S. club set out to solve the mystery--especially since the student artist has accused them of stealing it.