It’s no surprise that news of big increases in D.C. public school scores on the much-respected National Assessment of Educational Progress (NAEP) tests has been greeted with as much suspicion as applause. Those who care about D.C. schoolchildren have been disappointed too many times by gains that were not sustained.

But maybe it’s time for skeptics like me to lighten up a bit. The improvement in fourth- and eighth-grade math and reading from 2011 to 2013 was significant. It was measured by federally run exams that are regarded as cheat-proof.

Many D.C. teachers, parents and onlookers, including me, think that some school administrators must have tampered with answer sheets on the D.C. Comprehensive Assessment System (DC CAS) test in 2008, 2009 and 2010. The results on the DC CAS soared in 2008, then plummeted at many schools. The testing company found far more wrong answers being erased and replaced with right answers than research indicates is possible without subterfuge. Similar erasure patterns in Atlanta led to a Georgia state investigation that uncovered cheating, with teachers changing answers after kids went home. D.C. school district leaders sadly refused to accept the city’s erasure data as evidence of cheating and never did a serious investigation.

D.C. test security officials did make efforts, beginning in 2011, to keep answer sheets out of the hands of school administrators. At several schools, this was followed by a sharp drop in average scores, further proof of previous tampering and a message to miscreants that it might be time to try honest ways of improving their schools’ statistics. I think that is in part what the recent NAEP gains show: D.C. schools putting more emphasis on teaching than erasing.

I still want the cheaters rooted out, but I don’t think the school system is going to do it. It appears, while we wait for D.C. officials to release the latest erasure data, that tampering has been suppressed, at least for now.

It is harder to squelch widespread skepticism about improvement in the D.C. schools, particularly when officials welcome the new test score gains as a “breakthrough,” ignoring the fact that the new proficiency rates of 28 percent in math and 23 percent in reading for fourth-graders, and 19 percent in math and 17 percent in reading for eighth-graders, are still bad. We ought to be modest about score improvements. They tend to be up and down, year to year, even in schools of proven quality. We still don’t know how much of the latest gains in D.C. schools were made in traditional public schools and how much were made in the charters, which have almost half of the city’s public school students.

Why not view the D.C. schools as one system, traditional and charter, full of conscientious educators helping kids improve? We can quarrel over whether D.C. Schools Chancellor Kaya Henderson and her predecessor, Michelle Rhee, have been good for the city, but they get points from me for being the first to try to bring traditional and charter D.C. schools together. We need to keep Henderson. Switching leaders would set us way back, spending more years on somebody else’s pet schemes.

In the spirit of the coming holidays, let’s forget for a while our old feuds and celebrate the teachers who have led more D.C. children to proficiency in reading, writing and math. School system leaders may be clumsy at it, but they are sincerely trying to raise the quality of instruction and create more time for learning. That works if done right. Let’s not let our skepticism get in the way of doing what we can to make sure our schools get all the help they need and create traditions of rigor and persistence that will save us from future disappointments.

For previous columns, go to washingtonpost.com/class-struggle.