The ministry was keeping "an open mind" on whether it would build the primary school on one site and relocate Wakatipu High School to the same site, or find another site for the high school, national operations manager Kathryn Palmer, of Dunedin, said.
The ministry was seeking to acquire land suitable for the relocation and expansion of the overcrowded high school, but it had not decided what it would do with the existing buildings, nor decided if Queenstown Primary School would use them.
Ms Palmer said between $22 and $27 million would be sought as part of a future bid for capital from the ministry to buy land and build the primary school.
A total of 15 staff would be needed at the school, growing to 30 in line with pupil population.
The ministry does not own land between Queenstown and Arrowtown.
When asked why the ministry was waiting until 2021 to open the school when Wakatipu principals say their schools are bursting at the seams with pupils, Ms Palmer said primary school rolls had not grown significantly more than in 2008.
"With the opening of Remarkables Primary School in 2010, there is expected to be adequate primary school capacity.
"The change of school class at Wakatipu High School, from year 7 to 13 to a year 9 to 13 is anticipated to provide further capacity for future growth."High school board of trustees chairman Peter Doyle said this week predictions were the school would have more than 1000 pupils by the end of 2015 without years 7 and 8 included.
"To say we have another 10 years up our sleeves is ridiculous."However, Ms Palmer said ministry projections, based on projections commissioned by the Queenstown Lakes District Council and Statistics New Zealand, identified there would be sufficient capacity at Wakatipu High School until 2026.
"The student numbers in this area can change rapidly and this will continue to be monitored to ensure additional schooling provision is available just before it is required."
Between $65 and $70 million was needed to relocate the secondary school, including potentially buying a site.
The money would also be sought as part of a future bid for capital.
"The number of pupils the secondary school will be built for will be decided at a later date, depending on actual population growth. However, the initial costings at this stage were based on an initial roll of 1043 students, growing to 1250 students, from years 9 to 13."
