In a recent survey of college students on U.S. civic literacy, more than 81 percent knew that the Rev. Martin Luther King Jr. was expressing hope for “racial justice and brotherhood” in his historic “I Have a Dream” speech.

That’s the good news.

Most of the rest surveyed thought King was advocating the abolition of slavery.

The findings indicate that years of efforts by primary and secondary schools to steep young people in the basics of the civil rights leader’s life and activities have resulted in a mixed bag. Most college students know who he is – even if they’re not quite clear on what he worked to achieve.

Students and teachers say today’s federal holiday marking King’s birthday is the one that receives the most attention in schools, in part because the events surrounding the man it commemorates are the most recent.

A danger, educators say, is that lessons about King can become repetitive from year to year, especially when using the same theatrical performances and movies. As a consequence, many students know about King’s 1963 “I Have a Dream” speech but not about his seminal “Letter From Birmingham Jail,” also written in 1963.

The recent survey of college students, conducted by the University of Connecticut’s Department of Public Policy for the nonprofit Intercollegiate Studies Institute, suggests that schools are not doing as much as they could to go beyond a cursory history lesson. More than 14,000 college freshmen and seniors at 50 colleges and universities earned an average score of 53.2 percent in the survey.