Incidents of teachers assisting students as they took state standardized tests this year in Cannon Falls and St. Paul have led to the tossing out of nearly 50 exam scores, Minnesota Department of Education reports show.

At Cannon Falls Elementary, a teacher monitoring fifth-graders admitted to "helping students find the correct answers by writing on their scratch paper, giving definitions to math terms and telling students what 'type' of problem it was," according to a state report.

The teacher quit in May, citing personal reasons unrelated to the testing issue, and the math results for the 26 Cannon Falls students who took the Minnesota Comprehensive Assessments (MCAs) were thrown out.

"We take testing very seriously, and we want what's best for our kids," Superintendent Beth Giese said Thursday. "It's the first time we've ever had an incident."

At Linwood Monroe Arts Plus in St. Paul, a teacher/proctor was put on administrative leave after going beyond the role of simply reading test directions by "providing students with direct prompting and direction on test items while they took the test," the school district said.

Test scores for 21 seventh-graders were invalidated, as a result. On June 13, a Linwood Monroe seventh-grade teacher with the same initials as one placed on administrative leave on May 7 reportedly resigned, according to school board records.

Each year, students take the MCAs to chart the progress of schools and districts, and to monitor school improvement and accountability.

Scores do not affect a student's grades in school. Altogether, more than 500,000 Minnesota students take some or all of the tests covering math, reading and science.

Because of the incident in Cannon Falls, the elementary school will not receive a "school score" from the state Department of Education this year.

The department is required by statute to maintain the integrity of the MCAs, and as such, looks into reports of possible test security breaches — a process that has been in place since 2001, Department of Education spokesman Keith Hovis said. From what he understands, he added, this year was "fairly average."

From time to time, Hovis said, there have been reports of teachers assisting students, but he described them as isolated occurrences.

"Minnesota has been fortunate that we haven't seen large-scale malicious intent like you've seen in other states," he said.

A trend that has emerged, he said, is of students using their cellphones or venting about tests on social media as they take their exams.

At Avalon School in St. Paul, a student who was frustrated after just two questions wrote a "profane phrase" and took a picture of it with his phone, a state report says. His test was thrown out.