A bill that would block state plans to change how public high schools are graded died in the state Senate Education Committee on Thursday.

The measure, House Bill 466, failed to generate a motion after an hour-long hearing.

That means the House-passed proposal is unlikely to advance before adjournment on June 6.

Earlier this month the House approved the plan 70-28.

HB466 would block state plans that would make ACT scores — a measure of college readiness — a key part of how public high schools are graded starting this year.

It would retain the grading system the way it operated for the 2011-12 school year, which would exclude the ACT results.

Backers said the new rules would cause state-issued letter grades to drop a letter or two.

Opponents said all students benefit from taking the ACT and that Louisiana pupils have shown academic improvements when standards are raised.

Opponents included Gov. Bobby Jindal’s office, state Superintendent of Education John White and Chas Roemer, president of the state Board of Elementary and Secondary Education.