The Minnesota Department of Education recently released the latest round of student testing results. Overall, math and reading scores on the Minnesota Comprehensive Assessments (MCAs) remained flat, as they have for the past few years. In the 2015-16 school year, 59 percent of students were at grade level in math and 60 percent were at grade level in reading.

The state's response to the flat performance was troubling. According to the St. Paul Pioneer Press, the Education Department suggested that "the state may never boost the academic performance of students of color without first addressing the outside factors that hold children back in school."

This is a cop-out, essentially suggesting that schools are powerless to educate students who are economically disadvantaged or who face other challenges outside of school. Furthermore, it suggests that these students cannot be helped.

It's a defeatist mind-set that absolves our education system of responsibility to educate. It's also contrary to the experience of many schools that are successfully educating low-income students and students of color.

Minnesota's math, reading and science tests give families, educators, policymakers, and the public critical and objective information on how well students are progressing on our state's standards. In fact, the MCAs are the only tests that are specifically aligned to our state's rigorous academic standards.

But tests provide more than mere measurement. Since they are aligned to the state's academic standards, the tests also provide a road map to postsecondary success. In fact, students who meet benchmarks on the state's high school reading and math MCAs will soon be automatically exempt from remedial courses at Minnesota State (formerly MnSCU) colleges and universities. Currently, 25 percent of high school graduates end up taking postsecondary remedial courses to learn things they should have learned in the K-12 system, a wasteful cost to those students as well as their schools.

In short, the state's tests and academic standards provide a road map to students and educators alike. Without these tools, they are flying blind, and what students are taught in one school can differ significantly from what's taught in another school.

However, whatever one's interpretation may be of these test results, we should all be able to agree that measuring student knowledge and achievement is a critical part of a quality education. After all, you can't improve what you don't measure.

But if anemic MCA test scores are cause for concern, so are the students for whom we have no MCA test scores. That's because students in some districts are beginning to opt out of state exams altogether, particularly in high school.

It is a sign that the "opt-out movement" is gaining some traction. The opt-out movement is largely the result of a coordinated nationwide effort by teachers unions and their allies to eliminate information on student performance on state standards and to undermine school accountability and teacher evaluation systems. In Minnesota, the teachers union has made a concerted effort to encourage students to opt out of the MCAs. Unfortunately, it appears to be working — to the detriment of students.

According to the Star Tribune: "In the 2015-16 school year, 94 of every 10,000 students statewide refused to take the math tests, up from 3 per 10,000 just four years earlier. A lower rate of students refused to take the reading tests, but that has also risen sharply from 4 per 10,000 to 74 per 10,000."

Minneapolis appears to be ground zero for opt-outs. For example, according to the Star Tribune: "At Southwest [High School] last year, 95 percent of the 11th-graders opted out of the math test. As a result, only 12 students were tested; five of them scored in the range that is considered proficient (42 percent)."

Complacency may be partly responsible for higher opt-out rates. After all, the state's high school graduation rates have steadily increased in recent years, ostensibly a sign of academic progress. However, the increase in graduation rates followed the elimination of state basic skills test requirements in reading, writing and math to earn a diploma.

Consequently, one Minneapolis high school with a high opt-out rate also had an 87 percent graduation rate. Sounds good, until you learn that nearly 40 percent of these graduates who have gone on to a postsecondary institution have been required to take remedial reading and/or math classes.

Opt-outs have serious and negative consequences. Schools struggle to assess students' progress, policymakers struggle to hold schools accountable and parents are deprived of information they need to make informed decisions about their children's education.

Minnesota has created some of the best academic standards in the country. We've also created the MCA tests specifically aligned to those standards so families, educators and the public have consistent information about student progress. The opt-out "movement" is a cynical attempt to deny families and the public objective information and to sweep our state's massive student achievement gap under the rug.

Charlie Weaver is the executive director of the Minnesota Business Partnership, which represents the CEOs of Minnesota's largest companies.