The bus driver, identified by school officials as Debbie Duvall, was flown to a Fort Wayne hospital, where her condition was not available Friday night. The two truck drivers were not injured.
"It saddens the Twin Lakes School community to report the death of four of our students involved in a school bus accident today," said a statement issued by Superintendent Thomas Fletcher of the Twin Lakes School Corp. in nearby Monticello.
The bus was carrying special-needs students, the Logansport Pharos-Tribune reported. The students attended two elementary schools in Logansport, Fletcher said.
The crash occurred about 3 p.m. on U.S. 24 west of Logansport, about 70 miles north of Indianapolis, said 1st Sgt. Dave Bursten of the Indiana State Police.
A moped driver slowed suddenly in front of a dump truck, which tried to stop but clipped the bus in the oncoming lane, said state police Sgt. Tony Slocum.
The small bus flipped onto its side and into the path of a second dump truck, which struck its roof. The bus then slid into a ditch and came to rest, its front end and roof crushed.
The accident is being investigated.
The collision comes just days after police said a tractor-trailer driver on his cell phone hit a school bus in Florida, killing a 13-year-old girl.