Tell the children to pay attention. The latest round of protests against the South African government can teach them something of social history in this country; it can help them learn to appreciate irony; and it can drive home to them the fact that even nice, respectable people sometimes find it necessary to stop being nice and respectable.

Your children won't remember the sit-ins of the 1960s, so you might need to point out to them that direct action was the last-resort path taken by people who felt so strongly about issues that they were willing to defy the law (though, unlike today's abortion clinic bombers, they didn't try to escape the consequences of their actions).

The students who led the lunch- counter sit-ins of the '60s didn't want to go to jail, but it occurred to them that the lunch counters (and theaters and hotels and interstate buses) would remain segregated unless the matter could somehow be dramatized and made a national issue.

So it was with the people who, on the eve of Thanksgiving Day, began a series of anti-apartheid demonstrations by staging a sit-in at the South African Embassy. This time it wasn't student radicals who started the action but members of the establishment: a member of Congress, a member of the U.S. Commission on Civil Rights, the head of a well-respected Washington lobby and a former government official now on the law faculty of a leading university. And while there were no police dogs or fire hoses as in the '60s, three of the demonstrators did go to jail.

But it isn't enough to help your children understand the tactics behind the Free South Africa Movement, as the latest protest has been dubbed. You need to make sure they understand just what is being protested, and why this particular method has been resorted to.

They need to understand that apartheid is several times worse than the racial segregation that used to be called Jim Crow in the old South. Apartheid not only denies political, economic and social equality to South Africa's black majority; it even denies them citizenship in their own land. And the cost of protesting this unholy arrangement is, in South Africa, imprisonment and frequently much worse.

Your children need to know that one of the immediate goals of the protest in this country is the release of 13 black labor union leaders who were arrested during a recent two-day strike and haven't been heard of since. The demonstrators are also calling for the release of black South African leaders -- Nelson Mandela and Walter Sisulu -- who have been in jail since the 1960s when D.C. Del. Walter E. Fauntroy, Civil Rights Commissioner Mary Berry, TransAfrica executive director Randall Robinson and former Equal Employment Opportunity Commission Chair Eleanor Holmes Norton were protesting Jim Crow in the American South.

And one of their most important objectives is to get their own government to abandon its policy of "constructive engagement" toward South Africa, a policy that calls for U.S. officials to cluck their tongues at apartheid while doing business as usual with its perpetrators.

Your children need to understand that the current movement, like its 1960s prototype, is not a black movement (though it is black led) but a movement whose appeal is to everybody interested in human justice.

Your children will probably ask why the protesters didn't try to work through the system of which they are now a part. Tell them that they did; that attempts at legislating a new U.S. relationship with South Africa, attempts to influence the White House, attempts to negotiate with the South African ambassador, all failed. The demonstrations are a last resort.

Your children ight ask how nonviolent demonstrations succeeded in changing laws that had put such severe limits on the rights of black Americans. You can explain that the demonstrations worked by raising the consciousness of the American people and their national government to the point where the old way became morally untenable.

And if they ask you just whose consciousness is supposed to be raised now, when the administration that fathered "constructive engagement" has just been reelected in a landslide, well . . . children sometimes ask too many questions.