It is considered one of the real pressure points in education and schools and parents often have to wait weeks for specialist help.
Special Education Principals' Association president Judith Nel said she hoped any announcement would address the need for more training and well as immediate resources.
"We need far more professionals and resource to go into people at the coalface," she told the Weekend Herald.
The increase was not part of the 100-days plan, which has already been accounted for in the Government's books and so it will have to come out of the discretionary operating allowance, signalled in December to be about $2.6 billion for this Budget, although that is likely to be revised upwards on Budget day.
But the allowances also have to fund wage increases for the public sector.
Demands within the education sector, which has a $3.7 billion wage bill annually, will be contesting for that spare dollar.
In an interview with the Weekend Herald, Ardern said her first Budget as Prime Minister had been no different to any other in terms of spending.
"As with every other Budget, the ambition outstrips the available resources by quite some margin."
She repeated Labour's recurring theme of National having "under-invested".
"But for us now, we just need to get on with it," she said.
"The primary focus isn't the debate over what happened. It is just getting on with it.
"That's what I know voters need to see from us, that we've got a plan and if we aren't doing it in one go, what does it take, where's the emphasis, what are we really focused on?"
Conservation Minister and Green MP Eugenie Sage will make her announcement at a native bush reserve in Wellington.
Getting a significant increase in DoC funding was negotiated by the Greens in their confidence and supply agreement with Labour.
Funding in the current year — from Steven Joyce's 2017 Budget — is $466 million, which was a cut from the 2016 Budget of $481 million.