Rose Ashton-Weir was identified as a gifted student but began losing interest and started failing math in year nine at the Geelong Grammar School.

"I never developed the skills and they never instigated a system to help me rebuild those skills," Rose said.

Her mother Elizabeth Weir claims her attitude and her results improved quickly after she left the $45,000 a year boarding school to attend a Sydney TAFE College with $500 a year fees.

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"I had concerns about what happened at the school and I tried to communicate with the school about those concerns, and I found there wasn't an available complaints system," Elizabeth said.

"Honestly we're shocked that for $500 a semester you get better education than you get for $45,000 a year."

They are seeking compensation for school fees and relocation costs. The school argues it was not the tuition or support that was lacking but Rose's effort.

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A hearing continues before the Victorian Civil and Administrative Tribunal.

More stories from reporter Matt White

This reporter is on Twitter at @MattWhite_7