Premier Annastacia Palaszczuk was in Townsville on the third day of the campaign to promise $100 million to upgrade TAFE campuses and boost training programs.

Labor is sandbagging three ultra-marginal seats in the garrison city, where unemployment is a key issue at the October 31 state election.

Ms Palaszczuk's pledge includes $14.2 million for a hydrogen worker training facility at a local TAFE, which she says will help diversify the economy and grow jobs.

"I'm absolutely determined that we get those skills here in Townsville to make sure that people are ready for the next economic boom of hydrogen," she said.

"It's not just me saying this, the federal government is saying this and (Australia's Chief Scientist) Professor Alan Finkel has been saying this as well."

Sun Metals announced in July it would build the state's first hydrogen plant in Townsville.

The Labor government could fall if it loses just two seats, so it's campaigning hard to hang onto the local seats of Townsville, Mundingburra and Thuringowa.

In the state's far north, Liberal National Party leader Deb Frecklington offered her own vision for economic diversification.

She promised a $20 million ship lift for Cairns, which has suffered from a tourism downturn due to COVID-19, to support the marine maintenance sector

The ship lift would be Australia's largest and capable of lifting vessels of 5000 to 7000 tonnes.

Ms Frecklington wants Cairns to rival Darwin as northern Australia's defence hub in servicing navy vessels and Border Force patrol boats.

"This is partnering with the local industry to make sure that the infrastructure is built, so we've got a future economy, so we've got a growing of the economy," Ms Frecklington said.

The LNP are hoping to dislodge Labor from the local seats of Barron River, Cairns and Cook.

Meanwhile, the Katter's Australian Party and One Nation struck a preferencing deal in a bid to seal more crossbench seats.

The two minor parties will put each other second and the Greens last on their how-to-vote-cards.

"Queensland can't afford another four years of major-party dominance, we know it doesn't work, enough is enough, time's up," KAP state leader Robbie Katter said.

He also took aim at the LNP decision to preference Labor last, below the Greens, in every seat in the state.

"Up here in the north the LNP they say they are pro-coal, yet down in Brisbane they tell everyone they are anti-coal," Mr Katter said.

"The truth is they are preferencing the Greens and they can't have a bet each way."

The Greens, who have their sights on three inner Brisbane seats, unveiled a plan to fund free school meals by increasing mining royalties.

It comes after BHP and Origin Energy suspended their memberships in the Queensland Resources Council over the mining lobby's attack advertising against the Greens.

"We've heard a few multinational mining corporations complain about our proposal to increase royalties. Well here's the deal - we'll stop pushing to raise royalties when child poverty hits zero," Greens MP Michael Berkman said.

Queenslanders go to the polling booths on October 31.

Australian Associated Press