Premier Christy Clark says she sees a landmark Supreme Court of Canada decision that sided with the B.C. teachers' union over the province in a long fight on classroom conditions as an opportunity to invest in education.

"It's a chance for us to talk about how to invest more money in kids," Clark said in a weekend interview.

The decision ended a court battle that began in 2002, when the province used legislation to strip teachers of their right to bargain class size and composition. Christy Clark was the education minister at the time.

The B.C. Teachers' Federation challenged the constitutionality of that legislation, and the B.C. Supreme Court sided with the union.

That decision was overturned on appeal. But Thursday's Supreme Court of Canada decision marks the final ruling on the case — in favour of the union.

It means the province must restore staffing, such as teachers and librarians, to 2002 levels.

Province expected ruling, Clark says

The teachers' union puts the price tag for that restoration at up to $300 million.

The province has not provided figures on how much it is prepared to spend, but Clark said the government anticipated that a court decision might favour the teachers' union and set aside $100 million.

Clark said negotiations with the teachers' union will start soon.

"The idea that we want classrooms to be the right size, that we want more special needs teachers in classrooms, now is a chance to sit down and decide how we are going to make that happen," Clark said.

"Kids are only going to do better when we put more resources in."

With files from Richard Zussman