TORONTO -- The Ontario government is expected to make an announcement today that lays out its plans for the education sector, potentially including issues such as class sizes, sex education and teacher hiring.

Union leaders say they have not yet been given any details, but they expect to see cuts to help address a multibillion-dollar provincial deficit.

The education ministry told school boards earlier this month to defer filling vacancies for retirements and other leaves for teachers and other staff until an update from the minister.

The government has been consulting since January on class sizes and teacher hiring practices, including asking whether hard caps on class sizes should continue.

It's also been gathering feedback on a new sex-education curriculum, promising that a new one will be ready for the fall.

The Progressive Conservatives repealed a 2015 curriculum from the previous Liberal government that addressed consent, online bullying, sexting, same-sex relationships and gender identity.

Friday's education update is also expected to contain changes to the math curriculum, with Premier Doug Ford often talking of scrapping the so-called discovery math curriculum and "getting back to basics."