With all the activities now woven into the fabric of America’s commemoration of King Day — the speeches, the service projects, yes, even the shopping — there’s one aspect of the civil rights leader’s legacy that has been left at loose ends.

Sandy Horwitt means to change that, and he’s doing it one school at a time.

Horwitt has idolized the Rev. Dr. Martin Luther King Jr., ever since he was a college student in Chicago in the 1960s and worked for an organization established after King’s march for housing for the poor. These days, Horwitt’s activism is channeled through the Close-Up Foundation, a nonpartisan effort to provide voter registration, education and citizenship programs to high school students nationwide.

One day — he can’t remember when — he realized that his two passions were linked, that King’s long history of championing voting rights for Southern blacks could be the perfect vehicle for inspiring young people of all races to register and vote.

And Lord knows, King would be appalled that, 30 years after being granted the franchise, America’s 18- and 19-year-olds are voting at dismayingly low numbers. Fewer than half of the nation’s 3 million high school seniors are even registered by the time they graduate.

“My dream,” Horwitt says, “is to have voter registration be a prominent part of King observance every year.”

He took the first step last week, with a pilot program in 285 high schools in 30 states — including two schools in Pennsylvania — enlisting social studies teachers to discuss voting rights and give every eligible student the chance to register.

Results: About 10,000 students are now on the voting rolls.

That’s hardly a tidal wave, and it remains to be seen how many of these young people will actually cast a ballot, especially after leaving the encouraging cocoon of high school. Still, King knew better than anyone that reversing debilitating social trends requires time and patience — and persistence.

It took bloody protests, well-publicized arrests, stirring words, and incredible faith by King and others to persuade Washington that federal legislation was needed to counteract the pervasive denial of the vote to Southern blacks. As King himself wrote after his arrest in Selma, Ala., in 1965, “There are more Negroes in jail with me than there are on the voting rolls.”

How this precious, long-sought-for right became a disposable irrelevancy to so many Americans, particularly young people, is one of the great civic conundrums of our times. I would hate to think that voting is only fully appreciated when it is denied.

Better, instead, to applaud the efforts of teachers like Susan Finkboner of Council Rock High School South and her counterpart, Mike Pacitti at Council Rock North, who devoted class time and energy last week to the cause. Each aired a moving video provided by the Close-Up Foundation to their social studies classes, helped the eligible students register, and then watched as those students led a schoolwide registration drive.

Results: 169 students — and one adult — newly registered in the two schools.

Just as important as the number is the fact that students were encouraged to get involved by adults who clearly valued this kind of participation. “These habits of citizenship are not things picked up out of the air,” says Horwitt.

And clearly adults are doing a poor job of passing along those values and modeling the kind of civic behavior necessary to keep this complicated democracy strong. Civic education is edged out by our obsession with standardized testing. Political campaigns have been reduced to expensive television wars. Voter turnout ranges from embarrassing to pathetic.

King knew the power inherent in the act of voting. Would that our young people learn that lesson by our example.