In each of my grade school class pictures, there’s always one child a head taller than the rest of us. He or she was from a different state—usually the American South—and tended to have just moved into my rural Connecticut town. The reason these transplants towered over our class: They were older and their old school was so far behind the new school that they had to stay back a few grades. Yet the opposite tended to be true for children who migrated into our district from other countries: They were years ahead in math and were it not for weaker English skills, they probably would have skipped a few grades ahead.

Such a disparate education, depending on where you live, is one of the motivations for the Common Core standards. It sets benchmarks for what American students should know about math and reading at different grade levels. Forty-five states have adopted it and that’s already improving standards. Recent analysis claims that the Common Core standards are higher than the existing standards for 39 states in math and 37 states in English.

Some form of assessment is required to ensure Common Core’s standards are met, and that means testing. This week, the state of New York administered the tests—but that doesn’t mean every student took them. A parent-led movement to “opt out” swelled and gained traction. There are no official numbers but some advocacy groups claim the number could be as high as one-third of students opting out, with much higher rates in schools where children come from wealthier families.

But that is the wrong tactic.

As America addresses education reform, something that is long overdue and vital to maintaining competiveness, increasing the level and uniformity of education standards is essential. The difference in quality public education across states and counties is a disgrace. It entrenches income inequality and robs children of economic mobility.

Indeed there is legitimate concern about Common Core’s standards, are these the right standards? Do they stress reading and math too much? Do they make curriculum too rigid for the special needs of a particular class and community? The validity of assessment is also up for debate. Do the tests really measure what Common Core is supposed to be teaching? Does it introduce bias based on income or demographics?  Will teachers merely teach to the test?

How information from the tests will be used remains unclear. But there’s a possibility it will have consequences for the promotion of teachers and students.  That raises the question if these tests adequately measure teacher performance. Some teachers have classes composed of children whose parents aren’t engaged in their child’s education. Parent engagement is a key component of a good education. A teacher with a less engaged parent population has to do more work to compensate, but will never be able to make up the difference.  A state or national wide test won’t capture that.

But the concept of common standards and regular assessment should not be questioned. Blocking information because you fear how it might be used in the future does not help anyone. As the US moves toward uniform standards there will be a learning curve and some mistakes made. But the only way to get better is information and transparency.

Parents who “opt out” have done education reform a disservice. Like it or not, testing is the best way to produce uniform standards and accountability. Opting out is more common among higher income families. If the kids from rich families don’t take the test how can we know what poorer children are or aren’t getting from their schools?

Some are opting out because they worry tests are unpleasant and mak.... Some parents lament (without any irony) that they don’t like to see their child worry or that they don’t find school fun anymore. That is troubling because it sends the message if something makes you uncomfortable, you don’t have to do it, even if it’s for a greater good.

Skipping out on the tests also allows children to skip out on an early, important lesson: Sometimes, life requires doing things that invoke anxiety and being measured against our peers.  Tolerating discomfort and anxiety and learning to perform under those conditions is an important life skill.

Other parents are taking a more activist role because they oppose Common Core, or testing in general. They view opting out as an act of civil disobedience. Perhaps they should leave this to the education experts, those with experience and more information. When passionate individuals make up rules that don’t apply to them, the entire system can’t be measured.  Opting out ensures these tests will be biased and less effective—meaning less reliable information. Parents, to be sure, have valid concerns, but they are better addressed through community activism rather than non-participation.

Education secretary Arne Duncan has defended the Common Core, speculating that higher income parents fear information, the truth about their child’s abilities, or the real quality of local schools. That may be unfair, but more information is better and should not be feared. Parents are exercising their option, but that option shouldn’t exist.

You can follow Allison on Twitter at @AllisonSchrager. We welcome your comments at ideas@qz.com.