Studies show that lengthening class periods is not a proven means of raising standardized test scores.
Jeff Lindsay was a member of a citizens' group in Appleton, Wis., six years ago when a school administrator came to talk to the group about block scheduling. The concept, which involves changing school schedules so that students can have longer periods and fewer classes each day, was new to the group, and the administrator painted it in glowing terms.
"Aren't there any disadvantages?" Lindsay remembers asking. When the educator offered none, Lindsay, who has a doctorate in chemical engineering, went to the research literature to find out for himself.
What he learned, to his dismay, was that there were few large-scale, scientific studies to support the administrator's claims that block scheduling would improve student achievement. A few Canadian studies that Lindsay turned up even suggested the opposite was true. For all the enthusiasm that the local administrator had showered on the concept, Lindsay concluded it offered no guarantee that students learn more when their days are carved up differently.
"To make a change, you have to have a reason to change," says the father of four. "The burden of proof is to have solid, reproducible studies that show academic improvement with block scheduling."
Lindsay's discovery was news to him, but not to researchers who have long studied block scheduling. When it comes to improving student learning, the research on the subject suggests that block scheduling is not a sure thing. Hundreds of studies show that districts here or schools there raised test scores when high schools switched to a block schedule. But the prevailing view among U.S. researchers seems to be that lengthening class periods is still not a proven means of raising scores on standardized tests of student achievement.
"Parents sometimes chew me up because I can't guarantee these things," says Robert Lynn Canady, a professor emeritus of educational leadership and policy studies at the University of Virginia in Charlottesville and a well-known proponent of block scheduling. "I would say, from a research point of view, there are safer factors to talk about than student achievement."
Focusing only on test scores, proponents such as Canady argue, is taking too narrow a look at one of the most popular innovations to take hold in schools in recent decades. Even if block schedules do not clearly improve standardized-test results, studies suggest plenty of other good reasons to consider them.
Surveys over the years have shown, for example, that students feel less stressed and that their grades go up when their classes are longer. Principals report that discipline improves when students spend less time in the hallways, moving from class to class. And more flexible scheduling often means that students can take more courses over their high school careers and quickly retake the ones they fail.
"When I advise school districts and administrators I always ask them, 'What is it you want and why?'" says William R. Veal, an assistant professor of science education at the University of North Carolina at Chapel Hill. "Some may want to improve academic achievement, while others just want to provide more academic opportunities for students."
"That's why," he adds, "in some studies, block scheduling shows up as a poor option, where in other studies the same thing will show up brilliantly."
Variations on a Theme
If the research on block scheduling doesn't spell out a clear success story, one reason may be that the definition of a block schedule itself is muddy. Dozens of variations of block schedules exist; schools may even use several different schedules at the same time.
One of the most common types is the A/B, or alternate-day, schedule in which students take eight, yearlong courses, but attend classes for each of them only on alternating days. Monday, for example, might be taken up by physical education, science, English, and history, while Tuesday's schedule features French, algebra, music, and a second mathematics class.
With another popular block plan, students take just four courses at a time that meet daily but last only half a school year. So, students might take science in the fall and then not take another science class again until the following year. Such plans are often known as semester block plans, or 4x4 (pronounced "four-by-four") plans.
Despite such variations, the basic idea in every plan is to carve out bigger chunks of time so that students can study their subjects in depth, do more science labs, or undertake more of the action-oriented activities that cognitive psychologists say enhance learning. On a block schedule, for example, classes might range from as short as 60 minutes to as long as two full hours, compared with the average of roughly 50 minutes that students typically spend in each class.
Although block scheduling has been around for decades, interest in the concept was reinvigorated in 1994, when the National Education Commission on Time and Learning called on educators to use time in "new, different, and better ways."
"Used wisely and well, time can be the academic equalizer," the panel argued in its report.
But the real catalyst for the block-scheduling movement in recent years has been states' efforts to increase high school graduation requirements, says Canady.
"When you had a six-period day, as long as it only took 18 or 19 credits to graduate, there was no problem," he says. "But when you raise graduation requirements to 22 or 24 credits, that's a real problem."
Rather than trying to cram in more daily class periods to meet the new requirements, many schools have re-evaluated the way they carve up the school day. With most of the commonly used block schedules, students can usually take more classes over the course of the academic year, making it easier to meet the more stringent graduation requirements.
Canady and his colleague Michael D. Rettig, an assistant professor of education at James Madison University in Harrisonburg, Va., estimate that roughly a third of the nation's secondary schools use some form of block scheduling. In some states, such as North Carolina, that percentage is as high as 74 percent.
Canady says the block schedule is also gaining popularity where new requirements mandate that all students take and pass particular subjects, such as algebra, that have historically had high failure rates. On a modified semester block plan, for example, the brightest students can dispense with that requirement in half a year and go on to another math course. Students who need more time to master algebraic concepts, on the other hand, can take the course over two semesters, studying Algebra 1a the first half of the year and Algebra 1b the second half.
Taking more courses in bigger increments of time, however, might also mean that students get less face-to-face time with their teachers over the duration of the course—as many as 37 fewer class hours, according to some studies. That's another drawback that parents often don't hear about when the new schedules are introduced, says Lindsay of the citizens' group in Wisconsin.
Part of the problem in studying the academic benefits of block schedules is that so few researchers have taken the kind of hard, empirical look at it that Lindsay and other critics advocate.
"There are some good studies, but there aren't enough," acknowledges Veal of the University of North Carolina. "A lot of the studies are coming from school districts, and they're missing some of the rigor that is necessary."
Veal tries to introduce some measure of control into his own, ongoing studies on the subject by following a single, Midwestern school that is using three different schedules—a traditional schedule, a 4x4 block plan, and a combination of the two. That way, he says, any changes in school attendance, tardiness, or grading policies affect students on all three plans equally.
In 1997, the first year of the plan, Veal and his colleagues found, the students on the traditional schedule scored slightly higher than their peers on nontraditional schedules on state-mandated tests in mathematics. But that edge disappeared over time. By the end of the second year on the plan, students on all three schedules were performing about the same on tests given by the state in reading, language arts, and math.
Testing the Theory
The largest-scale U.S. study on the subject was conducted by the North Carolina Department of Public Instruction in the mid-1990s. It compared students in schools across the state operating on a block schedule—usually a 4x4 plan—with those in schools that had traditional schedules on state-mandated end-of-course tests. Because most of the schools on block plans tended to be poor and traditionally low-achieving, researchers adjusted the data to account for socioeconomic differences among students, says Carolyn T. Cobb, the evaluation section chief for the state education department.
According to the adjusted figures, in 1995, the first year of the study, the block students were outscoring the traditional students in most subjects tested. But that edge was whittled over time so that, by 1998, students from both types of schools were scoring comparably on tests in four of five subjects.
The exception was first- year algebra, which is required for graduation in North Carolina. In that subject, results were inconclusive because researchers had difficulty determining which students in block-scheduled schools had taken algebra in half a year and which students were taking a yearlong, stretched-out version of the course.
The most controversial studies on block scheduling come from Canada, where research involving 30,000-plus students suggests that taking classes on a 4x4 block schedule could actually have a slightly negative effect on students in math and science.
Canady and other supporters of block scheduling contend there are reasons to doubt those findings would hold up on this side of the border. For one, they argue, the Canadian classes, ranging from 60 to 80 minutes in length in one of the studies, were shorter than they are in most U.S. schools using the same sort of schedule.
For another, the tests were given in the spring, suggesting that students in the yearlong classes had a built-in advantage over students in the half-year courses. The argument is that the material tested would no longer be fresh in the minds of students who had taken the course in the fall. Also, students taking one-semester classes in the spring would be lacking more of the course's total content than students in the yearlong classes by that point in the school year.
Supporters also suggest that Canadian teachers got less time than U.S. teachers for professional development or lesson planning, and that the researchers failed to account for any socioeconomic differences among the schools studied.
Timing Is Everything
But Dennis Raphael, the researcher who conducted two of the Canadian studies in the mid-1980s, takes issue with some of those criticisms. For example, he doesn't buy the argument that the timing of the tests put students in half-year classes at a significant disadvantage.
His first study, published in 1986, examined math achievement in 250 Ontario schools using either 4x4 or traditional schedules. The second study, published a year later, focused on science achievement in 75 schools in that province. In both studies, students on the traditional schedules were found to fare better on the tests, which were given in May.
"We looked at all the possible confounding factors— geography, teachers' experience, socioeconomics—and found no differences," says Raphael, who switched fields and is now an associate professor in the school of health policy and management at the University of Toronto.
Even so, provincial governments in Canada paid little heed to the researchers' findings, Raphael says. In Ontario, for instance, virtually all public schools operate on a block schedule.
Test timing is a critical issue in much of the research exploring the connections between block scheduling and achievement.
Concerns crop up most often over Advanced Placement courses, which students can take in high school for possible college credit. Exams for that program, which is sponsored by the College Board, take place in May. That's a potential disadvantage for students who take their AP classes in the first half of the school year on a semester block plan.
To find out just how much of a disadvantage it is, the New York City-based College Board examined 1997 test data in four subjects: U.S. history, English literature, calculus, and biology. The researchers also used students' scores on the Preliminary SAT as a means of comparing students of similar academic abilities.
What they found, generally, was that students scored higher when they took their courses for an entire school year, regardless of whether they were doing it on a traditional schedule or an alternating-day block plan.
The study's other results were all over the map. Having taken a course more recently seemed to help in U.S. history, for example, but made no difference in calculus or biology.
But what the studies on the impact of block scheduling on student achievement lack in rigor, proponents suggest, they make up for in sheer volume. The literature is rife with case studies of more than 100 schools and districts that report positive results from switching to a nontraditional schedule.
"It's really what I would call an accumulation of a lot of different, little studies done by professors and graduate students," says Carol J. Freeman, who follows such work as a research associate at the Center for Applied Research and Educational Improvement at the University of Minnesota-Twin Cities.
"The point I think is important is that we can certainly show student-achievement gains in various individual schools," says Canady, the University of Virginia professor emeritus. "The schools that seem to be making the best use of scheduling to raise student achievement are those that see scheduling as a resource."
A case in point is Thomas A. Edison High School, an ethnically diverse, 1,650- student high school in Fairfax County, Va. Now in its eighth year using its own brand of block scheduling, the school recently was recognized for the gains its students have made on state-mandated tests.
The school uses a modified semester block schedule so that students can take band, chorus, journalism, and International Baccalaureate program courses all year long. Like the AP program, the IB program offers students high-level coursework, with tests taken at the end of the academic year.
Under the umbrella of the block schedule, struggling 9th graders can also take special courses in time management, test-taking, and study skills to prepare them for the academic road ahead.
"I think and believe our block schedule has supported our incremental growth in achievement in the high school," says Luke W. Fennell, the principal at Edison High. "It allows teachers to be with students 90 minutes a day, and most teachers only see 65 or 75 students a day. If we struggle in the first semester, we know what adjustments to make in the second semester, and we find we just keep getting better and better at it."
Experts agree, though, that whether a school makes a success of its nontraditional schedule has everything to do with what teachers do with the extra minutes they're given.
"Teachers need to vary their instruction," Canady says. "They need to know how to do a good Socratic seminar, how to use graphic organizers, how to use technology. That's needed regardless of the schedule, but it's more critical on a block schedule."
Teaching Style a Factor
In the North Carolina study, researchers found that most teachers on block schedules taught in much the same way as their colleagues on traditional schedules.
And that, researchers say, may explain in part why achievement does not always increase on the new schedules, or why parents often feel the concept has been oversold to them.
"Parents probably hear that teachers will change how they teach, and they don't," Freeman says. "And they probably hear from their kid that there's still a lot of lecture."
But the experiences of Jeff Lindsay, the Wisconsin parent, suggest school officials may be treading in dangerous territory when they fail to give parents the full story on the benefits and drawbacks of a new scheduling system. Unhappy about the limited information his citizens' group received, Lindsay decided to launch his own Web site on the subject.
"This is not a crusade," he says. "I just saw that no one was being given the other side of the story." Now, Lindsay has become something of a thorn in the side of block-scheduling proponents. His Web site gets an average of 5,000 hits a month, and he hears from parents nationwide who have used the information he has gathered as ammunition to fight scheduling changes in their own communities.
"This has become controversial enough that people who are against it will demand that you look at the research now," Freeman observes. And that, she adds, may be better for everyone.
The Research section is underwritten by a grant from the Spencer Foundation .
Vol. 21, Issue 5, Pages 38-40Published in Print: October 3, 2001, as Changing Times