Opposition education spokesman Michael Ferguson signed the pledge this morning at a rally in Brisbane Street Mall.

Premier Lara Giddings and Greens leader Nick McKim pledged their support for the agreement in Hobart on Monday.

Liberal leader Will Hodgman was absent at the Hobart rally.

Mr Ferguson said while he was not the state parliamentary leader, he was signing on behalf of Will Hodgman and all of his parliamentary colleagues and Liberal candidates.

``We've always supported Gonski,'' Mr Ferguson said.

``We will be pushing for every available Commonwealth dollar. It's what we demanded from the Labor-Green government, and it's what we would do in government.''

Signed now by each Tasmanian parliamentary party, the Gonski Pledge is intended to show commitment to:

 - Upholding the principles of the Gonski Review of school funding; 

 - Securing Federal Government commitment to years five and six of the Better Schools plan; 

 - Maintaining funding levels for education required under the Tasmanian Gonski Agreement; and

- Committing to ensuring the share of funding to public schools.