Richard Mohammed always thought of himself as a pretty good student.

He graduated from Olney High School in 2005 with a B-plus average and optimistically entered Bucks County Community College, eager to study nursing.

But assessment tests showed that his reading and writing skills were poor, and the college insisted he take two remedial courses in high school English to catch up.

"I can honestly say my high school didn't prepare me for college," said Mohammed, 24, of Feasterville, married father of a 5-year-old girl. "I was getting my butt kicked in college. I didn't have a proper background."

Like Mohammed, large numbers of high school graduates are surprised to learn the diplomas they were handed in June don't necessarily mean they're ready for college in the fall.

For many of them, there's a disconnect between what high schools require for graduation and what colleges seek.

Traditionally, that gap has been bridged by remedial courses - high school English, even middle school math - taught in college.

Nearly 45 percent of community college students and 27 percent of four-year college students have taken at least one remedial course, according to the National Center for Education Statistics.

Experts such as Thomas Bailey, director of the Community College Research Center at Teachers College, Columbia University, said his research showed that the remedial rate for community college students may be closer to 60 percent.

Why do so many students require so much help? Blame it on the kindergarten-through-12th-grade system, education experts say.

"If the job is done right the first time, in K-through-12, you don't need remediation," said Bob Wise, president of the Alliance for Excellent Education and a former governor of West Virginia. "Remediation is paying for the same education twice."

In a recent study, the alliance, a nonprofit organization that describes its mission as helping high school students be better prepared for college, estimated the national yearly cost of remediation at $5.6 billion.

In Pennsylvania, the cost of remediation is about $153 million annually. In New Jersey, it is $121 million. Typically, students need help in writing, reading, and math.

F. Joseph Merlino, a science-education expert with a local nonprofit group, blames K-through-12 problems on "the oppressive focus by school administrators on adequate yearly progress" - showing improvement on state standardized tests.

Meanwhile, Pennsylvania employers "are crying because they can't get good people," said Merlino, president of the 21st Century Partnership for STEM Education in Conshohocken, meant to advance achievement in science, technology, engineering, and mathematics. "The gulf between what kids do in school and what's needed in the workforce is becoming wider."

Some of that criticism was echoed by Ron Tomalis, Pennsylvania secretary of education.

"It's difficult to swallow that these kids walk across a stage at graduation and we say, 'You met all our standards to graduate,' then the first thing they do in a postsecondary school is take a sophomore high school level math course," Tomalis said.

"Parents have to pay for extra semesters of remediation, and a four-year degree becomes five or six years."

To improve the K-through-12 experience, Tomalis said, the Corbett administration would use various means, including tenure reform, to weed out unqualified teachers.

"We shouldn't mask nonqualified teachers or protect them behind a collective-bargaining agreement," Tomalis said.

Another option, which the Rendell administration had pushed, is to require students to pass state exams in six subjects before they graduate. Tomalis has said he favored delaying the spring launch of the Keystone tests for a year to make sure "our students are able to pass the test that . . . we're forcing them to pass."

Education experts said a central problem was the long-standing disconnect between high school and college.

The K-through-12 and college systems are misaligned, with colleges not explaining to high schools what they need, and high schools not knowing how to sharpen students to a college edge, experts say.

Though this is an old problem, the stakes are higher now. More students are seeking jobs in technical fields that require four-year degrees or certificates, said Elisabeth Barnett, a researcher at the Community College Research Center.

Thirty or 40 years ago, the country had many low-skill, decent-paying manufacturing jobs in the automobile and steel industries. A person could eschew college, work in a factory, and still afford a house, boat, and vacation, Bailey said.

"Those days are gone," he said.

In 1970, 6.2 million students were enrolled in four-year colleges in the United States, and 2.3 million were in community colleges, figures from the National Center for Education Statistics show.

By 2009, nearly 13 million students were attending four-year colleges, with 7.5 million in community colleges.

At Community College of Philadelphia, for example, enrollment has risen 12 percent in the last two years alone. And 70 percent of students there are taking at least one remedial course, according to Judith Gay, vice president of academic affairs.

Locally, the Philadelphia Education Fund has begun a program that brings high school teachers and college educators together to better align instruction.

Nationwide, experts are pinning their hopes on a relatively new initiative, Common Core State Standards, rigorous high school guidelines meant to connect with college expectations.

The standards require more in-depth critical thinking and writing, among other ideas.

So far, 42 states - Pennsylvania and New Jersey included - have adopted the voluntary standards since they were established in 2008, according to the National Governors Association, which helped draft them.

Until and if the standards take hold, remediation will remain the primary way to make students ready for college.

Community colleges argue that it's their job to provide access for even underprepared students, so that everyone has a chance to earn a degree.

"It's part of our mission," said Victoria Bastecki-Perez, interim provost of Montgomery County Community College.

Not everyone agrees. "It angers me to hear community colleges say it's their job to remediate," said Dane Linn, director of the education division of the National Governors Association. "It's a moneymaker for them. But it's not their core mission."

And it's not clear how many people remediation actually helps. Richard Mohammed would say it has made all the difference. He recently graduated from Bucks County Community College with a nearly 3.5 grade-point average. He's looking for some kind of nursing job. And he is aiming to earn a four-year nursing degree.

"The remedial courses really helped me," he said. "They showed me how to succeed in college."

Contact staff writer Alfred Lubrano at 215-854-4969 or alubrano@phillynews.com. Read his blog, "Joint Custodian," at www.philly.com/jointcustodian