The U. S. Department of Education delivered some good news last week: The nation's high school graduation rate is the highest it's been since 1976. If you plan to celebrate, keep it brief.

The bad news: A stunning number of those graduates is unprepared for college.

"On average, only 23 percent of students who take our English placement exams place into a college-level English class," said Mojdeh Mehdizadeh. "These are first-time students who come directly from high school. Math is a little higher."

Mehdizadeh is vice chancellor of education and technology for the Contra Costa Community College District, and her findings cut across Diablo Valley, Los Medanos and Contra Costa colleges. Because these are open-access schools, as district Chancellor Helen Benjamin reminds, no students can be denied for low scores. But neither can they enroll in classes for which they are unqualified. So they take remedial courses.

"So much of what we do is remediation," said Contra Costa College President Denise Noldon.

The biggest hurdle is in English language arts -- yeah, reading and writing -- which encompasses comprehension, critical thinking and composition. This hardly ranks as a surprise in the smartphone generation -- texting and Twitter have unraveled the English language -- but experts say another reason is the minimal writing required in high school.

"Some students don't know the fundamentals of constructing a sentence," Benjamin said.

Written assignments are unavoidable in college, from annotated term papers to timed essay questions. "There's a disconnect between what students have been prepared to do in high school and the expectations in college," Noldon said.

The problem is not new, and Benjamin fears it's growing worse. Pam Tyson, director of educational services for the county's office of education, agrees. She points to an overemphasis on English lit studies at the expense of expository writing.

"I think it's easier to teach literature and novels than writing," she said. "It's very time intensive, and it's a very individualized process."

Help may be on the way. California is one of 47 states to embrace a new educational approach -- the common core curriculum -- that not only sets standards in math, English language arts and literacy in social studies, science and technology, but also emphasizes writing.

"One of the revolutionary things is the way assessments are made," said Nicole Steward, a management assistant in the Pleasanton school district. "We're transitioning from fill-in-the-blank, true-false and multiple-choice to computer-adaptive questions, where students will write a reflective response to something they've read."

Pleasanton also now offers a senior expository reading and writing class to address deficiencies among those who scored poorly in the California Standards Tests as juniors.

It can't happen quickly enough for college educators, who lament the time spent on teaching freshmen what they should already have learned. Benjamin said students need to grasp the relevance of clear, coherent writing, and to explain how teachers can help them.

"We can create what we think will meet their needs," she said, "but if they're not buying into it, it's not going to happen."

And those happy graduation numbers won't mean a thing.

Contact Tom Barnidge at tbarnidge@bayareanewsgroup.com.