SA Greens push public transport rethink

Students using public transport to get to school in South Australia would travel free under a proposed plan by the Greens.

The election promise from the party would cost $8.5 million a year, leader Mark Parnell says.

"With 80 per cent of school students now being driven to school, it's time to re-think strategies to encourage more independence and give kids more exercise," Mr Parnell said.

The Greens also want to allow seniors to travel for free at all times, at a cost of about $1.5 million a year.

"Seniors already enjoy free public transport outside peak periods, however having to pay before 9am or after 3pm can be a disincentive to older South Australians who undertake volunteer work," Mr Parnell said.

South Australia heads to the polls on March 17.