PHOENIX (AP) -- The Legislature has approved a bill to again let thousands of Arizona high school students use good grades to augment their "AIMS" test scores, and Gov. Janet Napolitano said she'd sign it into law.

But in a development that raised questions about when affected students would receive diplomas, the House's 35-21 vote Wednesday approving the bill (HB2008) fell five votes short of that needed to allow the measure to take effect immediately once signed by Napolitano.

Officials said that means districts would not be able to give affected students diplomas until 90 days after the current legislative session ends. The session will likely end within the next month or so, meaning that those diplomas would not be distributed before September.

The bill's sponsor, Democratic Rep. David Schapira of Tempe, said it was unclear how the delay would affect higher education opportunities or other plans for the estimated 5,000-6,000 students.

However, "once the governor signs it, we know these kids are getting diplomas," he said.

Arizona high school graduates must pass the AIMS test to get a diploma. Short for Arizona Instrument to Measure Standards, AIMS tests a students' knowledge of state curriculum on math, reading and writing.

The bill renews a program that was used during the first two years of the high-stakes graduation requirement. It allows a student to boost his or her AIMS test scores by adding points based on good grades in required courses.

The bill retains the previous program's ceiling of 25 percent on individual subject components of the test, but it would drop to 15 percent in the 2009-2010 school year and to 5 percent in 2010-2011 and thereafter.

To qualify for augmentation, a student must complete all required courses, have taken the test each time he or she was eligible and participated in any available tutoring or other remediation programs.

Napolitano, in telling reporters she planned to sign the bill, said timing was a concern.

"It's so late in the school year and so close to the graduation (that) it would be really unfair to seniors this year not to sign it," she said.

Added Napolitano: "They've otherwise passed their courses. They're otherwise making plans. The issue is whether they get to walk across the stage next week or two weeks from now and get their diploma. In my view they ought to get their diploma."

The Senate had approved the bill Tuesday with enough votes to make it take effect immediately.

The House vote fell short of the two-thirds vote needed for emergency measures because of stiff opposition from members concerned it weakened the test's value as an accountability measure for both students and schools.

"This sends absolutely the wrong message," said Rep. Sam Crump, R-Anthem. "A diploma from our high school is not a right. It's something that you earn."

Supporters defended it as a way to help students whose futures would be limited because they narrowly missing passing one or more parts of the test despite strong efforts in school.

"Without that diploma we are sending these young adults into a place where they are not going to be able to achieve," said Rep. Theresa Ulmer, D-Yuma. "We're basically saying if you're not the best and the brightest, you're not of value."

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