On this day, Aguilar had invited a student to the board to divide two fractions — a topic on the upcoming state exam. As his classmates compared notes in whispers, the boy wrote out his answer. Aguilar turned to the class.
"Yes!" they called back in unison.
"Good," he said softly, allowing a faint smile. "You know this."
John Smith's students in Room 25 were studying fractions too.
Speaking in a slow cadence, he led his class in reciting a problem aloud twice. He then called on a student slouched in the back. The boy got the answer wrong.
"Not so much," Smith said dryly, moving on to another pupil without explanation.
It was only 11a.m., and already it had been a tough day: Three of Smith's students were sitting in the principal's office because of disruptive behavior. All were later transferred permanently to other classrooms.
In an interview days later, Smith acknowledged that he had struggled at times to control his class.
"Not every teacher works with every kid," said Smith, 63, who started teaching in 1996. "Sometimes there are personality conflicts."
On average, Smith's students slide under his instruction, losing 14 percentile points in math during the school year relative to their peers districtwide, The Times found. Overall, he ranked among the least effective of the district's elementary school teachers.
Told of The Times' findings, Smith expressed mild surprise.
"Obviously what I need to do is to look at what I'm doing and take some steps to make sure something changes," he said.
Jobs with security
Public school students are graded and tested all the time. Schools are scored too — California rates them in an annual index.
Not so with teachers.
Nationally, the vast majority who seek tenure get it after a few years on the job, practically ensuring a position for life. After that, pay and job protections depend mostly on seniority, not performance.
Teachers have long been evaluated based on brief, pre-announced visits by principals who offer a confidential and subjective assessment of their skills. How much students are learning is rarely taken into account, and more than 90% of educators receive a passing grade, according to a survey of 12 districts in four states by the New Teacher Project, a New York-based nonprofit.
Almost all sides in the debate over public education agree that the evaluation system is broken. The dispute centers on how to fix it.