Matt Van Scyoc hit three 3-pointers and finished with 15 points for Indiana State (6-6), which has won three in a row after losing four straight.
Scott hit a pair of 3s during an 18-6 first-half run to put the Sycamores in front 30-18 with 5:48 left. They went into the break leading 33-24.
Ball State (7-4) pulled within five twice early in the second half and cuts its deficit to 60-53 with 5:23 to go but Van Scyoc hit a three and Smith scored five during a 9-3 spurt that pushed the Indiana State lead back into double figures and Ball State never threatened again.
Franko House led Ball State with 15 points. Jeremie Tyler added 13 while Jeremiah Davis and Bo Calhoun scored 10 apiece.