A 21-year-old woman and a 21-year-old man were treated in Taupo Hospital and later discharged.
The families of all of the students involved in a fatal road crash have been notified of the tragedy.
The group in the second vehicle were also Boston University students except for one man who is from another American university visiting a friend.
The students were traumatised by the crash and were being supported by police, victim support and exchange programme co-ordinators, said police.
"We fully appreciate the added pressure on families when their children are hurt or killed overseas. We have made it a priority today to contact the families as quickly as possible so that they don't hear the news through the grapevine, and to reassure other families who have children studying overseas,'' said Road Policing Manager Inspector Kevin Taylor.
Police would continue to ensure the families to receive the support they needed, he said.
The students were all studying a range of academic subjects, and as part of the exchange programme spend two semesters overseas.
Early indications from the scene examination show the vehicle drifted to the left into gravel, then over corrected and the momentum caused the vehicle to roll. It was not yet known why the vehicle drifted left, said Inspector Kevin Taylor.
It was unconfirmed if the occupants of the people-mover were wearing seatbelts, but the fact that some were thrown from the vehicle indicated at at least some of them were not, he said.