The Fort McMurray Public School District came up with the proposal to help save as much as $1 million on things such as busing and support staff.
The plan would have increased the average school day by 11 minutes and cancel classes for students on 15 out of 31 Fridays during the school year.
But trustees voted 3-2 on Tuesday against the shorter model, which was being called a "compressed week."
Board chair Jeff Thompson said he believed the trustees were swayed by the concerns expressed by parents leading up to Tuesday night's meeting.
"I think parents were deeply concerned about some of the issues around child care. How were they going to manage in a community where we have a number of shift schedules and parents are coming and going?" Thompson said.
"What was the impact going to be on their family life?"
The board pondered a compressed school week for its 5,400 students about two years ago but decided against it. It's now facing a $4.4-million budget deficit due to restructuring of provincial grant money and growth pressures in the oilsands city.
Thompson, who was one of the two trustees who voted for the compressed week, said the deficit this year will be absorbed by the board's $7-million reserve. But he said the problems won't go away.
"We have to address our fiscal shortfall and doing nothing doesn't change our problem," he said.
The separate school system in Fort McMurray already runs on a four-day week. Some schools in southern Alberta — in the Golden Hills and Palliser school divisions — also operate on a compressed calendar.
The Fort McMurray public district's 13 schools would have shuffled professional development days and made other scheduling changes to meet the number of instruction hours mandated by the province.
The board held several public meetings and deputy chairman Glenn Cooper said the response was overwhelmingly negative.
Some parents voiced concerns about a drop-off in student learning, in addition to the child care concern.
Thompson said there were also some parents who questioned if a shorter week would send the wrong message to students.
He said those parents suggested it would give students the idea that they could expect a four-day week in the real world.
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