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Undergraduate Education


Block plan compresses one class into a few weeks for deeper learning

Schools are adopting the 50-year-old strategy to curtail COVID-19 disruptions

by Celia Henry Arnaud
July 3, 2020 | A version of this story appeared in Volume 98, Issue 26


An illustration of a chemistry student going through four months of a block plan schedule.
Credit: Mike Reddy

During a typical semester, students take four or five classes at a time—for example, General Chemistry, Calculus I, and electives. So the professor for, say, General Chemistry doesn’t have students’ undivided attention.

But imagine if students took only one class at a time. The General Chemistry professor would have flexibility. The professor could schedule students to spend mornings in class and afternoons in lab. Or students could spend one day in the lab and the next in the classroom. The professor could go deeper into the course material than would be possible in a 50 min class.

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This situation isn’t completely hypothetical. Certain institutions deliver classes one at a time to students using a strategy called a block plan. The catch? Each class lasts only 3½ weeks—18 class meetings. Under this one-course-at-a-time model, professors do indeed get their students’ undivided attention. But they also need to manage what some call an “intense” experience for both professors and students.

This year marks the 50th anniversary of Colorado College moving to a block plan. Located in Colorado Springs, the college saw the one-course-at-a-time approach as a way to reduce class sizes, reduce competing priorities for students, and deepen the learning experience, according to Susan Ashley, a professor emeritus of history at Colorado College who is writing a book about the college’s implementation of the block plan. Since the college launched the strategy, a few other colleges and universities have moved to a similar schedule. Most recently, Victoria University in Australia completed a 3-year transition to a block plan. And now, in response to COVID-19, the disease caused by the novel coronavirus SARS-CoV-2, additional colleges are adopting various types of block plans. One reason behind the switch is to minimize the number of students who interact at any one time, limiting their risk of becoming infected. Another reason is to minimize the extent to which the pandemic disrupts classes; for instance, if an outbreak occurred on campus, only one or two classes would be affected for each student.

Despite the benefits, the prospect of teaching and taking chemistry in a block plan can be daunting. A day on this type of plan is the equivalent of an entire week on a semester calendar. In a typical block, classes start on a Monday and end 3½ weeks later, on a Wednesday. After a 4-day break, the next block—a new class—begins.

A tale of two schedules

Six weeks in a regular semester schedule are the equivalent of six days in a block plan. In these example schedules of an Organic Chemistry I class, students have more class time (not including the exams) in a block plan than on a conventional semester calendar. The courses cover the same topics but in a slightly different order.
Source: Jai A. P. Shanata
Source: Jai A. P. Shanata

During a block, professors have great freedom in how they allocate time in their course. “Pedagogically, we can do what makes sense for the students,” says Charles A. Liberko, chair of the Department of Chemistry at Cornell College, an institution in Iowa that has been using the block plan for 42 years. “We don’t have to break everything into 50 min chunks.”

Professors can hold lecture and lab on different days, front-load the block so they hold lectures for the first 2 weeks and lab for the third week, or move back and forth seamlessly between the two. They are able to integrate lecture and lab as much or as little as they want. “The break between lecture and lab gets blurred,” says Habiba E. Vaghoo, chair of the Department of Chemistry and Biochemistry at Colorado College.

Courses within a block plan take up at least as many in-class hours as those under more conventional semester schedules. Because a block plan compresses those hours into a shorter calendar, though, faculty have to be very deliberate in what material they choose to cover.

I really like the aspect of just focusing on one class and just putting everything you’ve got into that class.
Ayush Chitrakar, biochemistry major, Colorado College

“You cannot just take all the material that would have ordinarily been covered in a semester and cram it into 18 days. New faculty try that sometimes. We warn them not to,” Liberko says. “There just isn’t that time to digest it. So, quite frankly, we cover less material with one course at a time than they do on the semester. But I would argue that we cover that material much more deeply.”

Vaghoo agrees. “We have to pay a lot of attention to what we’re covering, why we’re covering it, and focus more on the process of learning, developing time management skills and critical thinking skills,” she says.

And just like professors can’t cram in all the material from a semester class into a block, neither can they lecture at students for hours on end. Instead, professors tend to use “short bursts of lectures intertwined with activities, worksheets, group work, things like that, so that [students] are learning the material,” Vaghoo explains.

As Colorado College hoped when it launched its strategy 50 years ago, the block plan has had benefits for students. Ayush Chitrakar, currently a rising junior at the college, says, “I really like the aspect of just focusing on one class and just putting everything you’ve got into that class. In my organic class, every week we had one test that covered five or six chapters. There’s no room for you to fall behind. You have to stay on top of it.”

The flexibility of a block plan also means that students can decide relatively late in their undergraduate education what they’d like to major in. For instance, a student in their sophomore year could take the entire general chemistry and organic chemistry sequence in one semester, which can go a long way toward catching up late starters, Vaghoo says.

Jai A. P. Shanata attended Cornell College as an undergraduate and now teaches there. Before joining the faculty at Cornell, though, he taught at a university on a regular semester calendar. Having experienced both teaching structures—as both a student and a professor—he believes that top students likely learn less on a block plan than they would on a regular semester calendar. But he thinks average students and struggling students learn more.

You cannot just take all the material that would have ordinarily been covered in a semester and cram it into 18 days.
Charles A. Liberko, chair, Department of Chemistry, Cornell College

With a block plan, Shanata can devote extra time to struggling students, because he knows they don’t have competing priorities. “I’ve never failed a student in Organic Chemistry” at Cornell College, he says.

On the other hand, professors teaching a demanding course like Organic Chemistry on a block plan can’t plan to “steal time” from other courses as they often do on regular semester schedules, Cornell College’s Liberko says. “When I took four courses [on a regular semester schedule] as an undergraduate, I didn’t spend one quarter of my time on each course. I probably spent more than half on organic chemistry,” he says. With a block plan, “we have to pare back what we expect the students to do because we can’t steal from those other departments that normally let us steal from them.”

Teaching a course in the compressed calendar of a block plan requires careful consideration not only of what material to include but also of how to organize that material. Emma Davy, a physical sciences tutor at Quest University, a small university in Canada that uses a block plan, thinks of her courses in terms of narrative arcs. (Quest calls its faculty tutors instead of professors.) “I pick an overall narrative. I pick a weekly narrative. And I pick a daily narrative,” she says. Within those narratives, she includes “legacy topics” that students need to succeed in later courses, whether in chemistry or other sciences. “Because Quest is so small, I can go talk to a geologist and ask, ‘What do students need to be successful in your class?’ ” she says. She then adjusts the emphasis and examples taught in her course to fit the interests of students in a given block.

The block plan works differently at Victoria University. By far the largest institution to use a block plan, it is primarily a commuter, rather than residential, institution. The university adopted a block plan with the goal of improving student learning outcomes and retention. For lab courses, there are eleven 3 h classroom sessions and seven 2 h lab sessions. The chemistry courses are primarily service courses for programs in biomedical sciences and general sciences.

Domenico Caridi and Stephen W. Bigger teach general chemistry in Victoria University’s First Year College. In combination with the transition to the block plan, Caridi and Bigger switched to using a flipped classroom pedagogy, a method in which students access online course materials on their own time and work problems individually and in groups during class meetings.

“We did need to fine-tune the content coming from our previous lecture format to the block,” Caridi says. “We did do a little bit of trimming, both in the theory and in the lab classes. But we haven’t lost any rigor.”

What they did need to do, Bigger says, was decide how to divide content among the classroom, lab, and students’ independent learning. “We can be highly selective in the choice of material in our unit,” he says. “We’re not watering it down. We’re treating it in a different way.”

When Victoria University switched to the block plan in 2018, students’ grades improved and attrition decreased compared with previous years (Student Success 2019, DOI: 10.5204/ssj.v10i1.1048). The university switched to a block plan over 3 years, starting with its First Year College. This year marks the completion of the transition.

Much like colleges around the world, institutions using block plans found themselves pivoting to remote learning in response to the COVID-19 pandemic. To adapt, many of the professors used a flipped format in which they delivered material via recorded lectures and used class time for the students to work together in Zoom breakout rooms.

Colorado College shortened the blocks to 15 days rather than the normal 18. Vaghoo and her colleagues hope such truncations won’t continue in the fall. “Three and a half weeks is a challenge even in person. When we shrank it even further to 3 weeks, it was quite a challenge,” Vaghoo says. “I think my colleagues will agree that, going forward, we need to keep our 3½ weeks.”

Davy, at Quest, delivered live video lectures during class time this spring, but she recorded the lectures, so students could access them later if they needed to. “I found that I had 12, if not more, of the 15 [students] every day,” she says. She shortened the daily meetings to 2 h and did all the classwork in the first 2 weeks, saving virtual lab work for the third week.

Several US colleges have announced that they will be adopting some type of block plan in response to COVID-19. Part of the rationale is that students will have fewer classes to manage at a time, easing anxiety, and, for in-person classes, they’ll come into contact with fewer people at a time. Another reason to adopt a block plan is that compressing courses into shorter calendars will lessen the disruption if colleges start the semester on campus but the pandemic forces them to return to online instruction, or if they start online but can move back on campus later when it’s safe. Colleges might be able to finish a module in one delivery mode—in person or online—before changing delivery modes for the second module.

Beloit College, in Wisconsin, the first to announce such a decision, will be dividing its normal semester into two 7½-week modules. During each module, students will take two courses. For lab courses, professors will be able to work with students for 3 h a day, 5 days a week.


During the first module, Theodore J. Gries, chair of the Department of Chemistry, will teach an advanced biochemistry course. The 3 h blocks may make labs easier, he says, because there will be fewer time constraints. “I’m excited to try the format with my classes,” he says. “We have a lab-centric chemistry curriculum at Beloit.”

Macalester College, in Saint Paul, Minnesota, has adopted the same approach as Beloit. “There was a sense that dividing semesters into halves gives us more flexibility in scheduling and [allows us] to be responsive to changes in public health guidelines,” says Keith T. Kuwata, chair of the Department of Chemistry at Macalester.

The College of Saint Benedict and Saint John’s University, a pair of Catholic institutions in Minnesota that share faculty, will be doing the one-course-at-a-time block plan. “We are still very much in the planning phase and cannot comment on the effectiveness of implementation of the block schedule at this time,” according to T. Nicholas Jones, chair of the Department of Chemistry. “Leaders in the CSB/SJU Chemistry Department are working tirelessly to ensure that students continue to make progress in their coursework during this crisis.”

Professors who already teach on the block plan offer advice to those who now find themselves thrown into a more accelerated schedule, whether that schedule is the one-course-at-a-time version or something else.

Cornell College’s Liberko notes that teaching under a block plan is labor intensive. Even with classes capped at 25 students, Cornell typically has separate instructors for lecture and lab in General Chemistry. “You need a lot of people to be able to pull this off,” he says.

And that intensity means that you need to prepare for the whole block ahead of time, Colorado College’s Vaghoo says. You can’t start the class and expect to plan as you go along, she says. “You’ll probably be working long days,” she says, and won’t have time to plan.

Davy recommends building a “flex day” into a block. It buys time if you’ve fallen behind, or it can be easily converted to a study day or day focused on real-world applications, she says. “Sometimes you feel like, ‘Oh, I’m taking a 3 h day and I’m putting nothing there,’ ” she says. “I promise you it will get filled. I’ve never built a flex day that wasn’t the busiest day of my block.”

This year has marked an unusual confluence of milestones for the block plan model—the 50th anniversary at Colorado College and the completion of the transition at Victoria University, the newest and largest adopter. The coronavirus pandemic has also brought attention as institutions seek options for dealing with unusual times in academia. It’s hard to predict whether the 2020–21 academic year will produce converts or critics.


This story was updated on July 20, 2020, to remove a photo of two students at the request of their university.


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