The comment was made during budget estimates hearings in the Legislative Assembly on Friday, where several community and industry groups gave their take on the 2019-20 budget.

Property Council ACT executive director Adina Cirson told the committee that a statutory requirement for the Suburban Land Agency to only sell land at market rates meant big and small developers could not make three bedroom freestanding homes stack up.

The territory has for several years faced sharp criticism from the industry and former Chief Minister Jon Stanhope, among others, as Canberra's land prices have more than doubled since Treasurer Andrew Barr took on the portfolio.

Ms Cirson, who formerly worked for the government, said the government needed "greater skin in the game" in terms of what price it sold land for, given the territory arguably had more control over land prices than any other jurisdiction.

She said the industry wanted to help deliver more affordable housing, but the government would need to take a lower price when the agency sold blocks in order to do that.

"At the moment, it is very difficult to make the affordability targets on the current land release program stack up," she said.

The call comes after the former Northbourne Flats site failed to sell, because the preferred tenderer could not meet the reserve price. The government said it could not lower the price as it was the market rate.

The council also again highlighted the effects of rising commercial rates on commercial land owners, many of which were forced to invest elsewhere or pass on the costs to tenants who then struggled to afford it.

Meanwhile the committee also heard Canberra teachers do not have the training to weed out gifted students, with children from poorer and non-English speaking backgrounds more likely to miss out.

Elizabeth Singer from the ACT Gifted Families Support Group told the committee schools were not spending enough on gifted students or training their teachers to identify them.

The fact there were no female students in H-course maths last year showed there were problems with early identification of gifted children, she said.

"The research tells us that if we have a teacher and we train them about gifted education, they'll correctly identify nine out of 10 students as gifted if they've got the gifted students in their classroom," Ms Singer said.

"If the teachers don't have that pre-service training they're only picking up three of the 10. The ones they're missing are from the backgrounds where their parents aren't likely topic them up., where English is a second language, where they're from low socio-economic families.

"There were no female students in H-course maths last year. There are the same number of gifted girls as potentially gifted boys, where did we miss out?"

Ms Singer said funding for gifted students should be a separate line item in the budget and should be reported on separately.

The hearings continue on Monday.