Teachers unions and other critics of federally required standardized tests have behaved in recent years as though killing the testing mandate would magically remedy everything that ails education in the United States. In reality, getting rid of the testing requirement in the early grades would make it impossible for the country to know what if anything children were learning from year to year.

Congress understood this fundamental point, and kept the testing requirement, when it reauthorized the No Child Left Behind Act — now called the Every Student Succeeds Act — last month. But lawmakers ducked the most important problem: the fact that most states still have weak curriculums and graduation requirements that make high school diplomas useless and that leave graduates unprepared for college, the job market or even meeting entry requirements for the Army.

The costs associated with this problem are demonstrated in a recent report by Motoko Rich in The Times, which focused on Berea High School in Greenville, S.C., where the graduation rate has risen to 80 percent, from under 65 percent just four years ago. But college entrance exams given to 11th graders last year showed that only one in 10 students was ready for college-level reading and only about one in 14 was prepared for entry-level college math. On a separate job skills test, only about half of students demonstrated the math proficiency needed to succeed at most jobs.

With results like that, it’s no wonder some South Carolina business leaders are worried that the state is producing high school graduates who are not qualified to compete for higher-skilled jobs at companies like Boeing, Volvo and BMW.