Mind and Hand and Ears

Collage of a Pure Data patch, consisting of several labeled boxes connected by lines, overlaying a black-and-white photo of a steam locomotive with steam blowing up out of the whistle.

One of the sound design exercises in 21M.380 challenges students to synthesize a steam train drive-by, with each group working on a different sound related to that problem. (Steam train photo is in the public domain, from Flickr Commons.)

By Joe Pickett, OCW Publication Director

People love sound effects. They have for generations. Just think of the original King Kong’s roar, created for the 1933 film by weaving together lion and tiger roars and playing them backwards. What would the movie be without that signature sound?

Certain sound effects are so iconic they have legs, so to speak. Like that bird whose call tells you the setting is deep in the jungle, no matter the continent. Or the scream of the guy who meets his doom by being attacked or falling from a cliff. That same scream has been used again and again in over 50 years of movies.

And what about those sounds that must be fully imagined? Like those space ships careering across the galaxy? The sound of the engines is so compelling the audience is happy to forget that, in the vacuum of space, sound does not exist. How did that sound get made?

Actually, it was designed. Design is a key part of the MIT “mind and hand” education. The art and science of sound design is the subject of 21M.380 Music and Technology: Sound Design, the latest in a series of courses on sound and technology that OCW has up on its site.

This most recent publication reflects the teaching of Dr. Florian Hollerweger, a sound artist and sound technology researcher in MIT’s Department of Music and Theater Arts.

Teaching with Technology (and Without)

The course site has lecture notes, readings, assignments, and samples of student projects through multiple iterations, so you can see how the projects evolved. MIT students and OCW learners alike benefit from the course’s use of a free open-source program called Pure Data. Dr. Hollerweger’s extensive notes include linked audio samples and working examples of Pure Data code, creating a dynamic learning experience.

Dr. Hollerweger explains the central practice of the course in the Instructor Insights on his This Course at MIT page:

 . . . we take real-world sounds and try to understand how they work. We then recreate them from scratch without using any recordings. Instead we rely on oscillators, noise generators, and filters, which we control through computer programs that students learn to write as part of the course . . . The prospect of engaging with students in the process of aestheticizing everyday sound experiences was a major impetus for teaching the course.

Learning to Listen

Before creating sounds, students must first learn how to listen. Or, as Dr. Hollerweger puts it, “Your main tool for sound design is really your ears.”  The soundwalk assignment is where it all begins. The students

 . . . describe, in as minute detail as possible, their aural experience from a listening excursion that we conduct across the MIT campus together. This assignment teaches them to verbalize their sonic impressions and communicate them to others. It trains students’ ears to attend not only to individual sound sources, but also to flutter echoes, comb filters, and other subtle acoustics effects that are due to the abutting architecture.

In other Instructor Insights, Dr. Hollerweger explains how he uses surveys to get to know his students and to tap their various talents, how he gets them learning actively in groups (he employs only the shortest of lectures), how he teaches the iterative design process, and how he assesses and grades creative projects.

Offering Advice

A lot of the instruction takes place the old-fashioned way—meeting one on one during office hours:

A lot of the support I offer students during the design process occurs during office hours. This is because their projects are so individualized. Every student has to come up with their own idea. When a student gets stuck, we need to get together to identify the key challenges of their design through an open-ended discussion.


21M.380 is but the latest course in which instruction in the iterative design process is represented on OCW. Some other recent examples are CMS.611J Creating Video Games, 6.811 Principles and Practice of Assistive Technology, and 20.219 Becoming the Next Bill Nye: Writing and Hosting the Educational Show.

Girls Who Build Cameras Have More Fun

Photo of several girls around a table working on some electronics.

Girls in the workshop working together to build their Raspberry Pi cameras. (Courtesy of Jon Barron, MIT Lincoln Laboratory.)

By Joe Pickett, OCW Publication Director

Kristen Railey is on a mission. She wants to help more girls become engineers and appreciate the wonders of engineering. But rather than simply joining the chorus lamenting that women are underrepresented in STEM fields, Railey is actually doing something about it. She’s created Girls Who Build.

Girls Who Build is a workshop in which high-school girls learn about engineering through things they use every day and then apply that knowledge to create new things on their own—all in a single day. It’s an exciting and fun experience for female students who may have very little exposure to engineering and who may not know any real engineers.

The workshop offers the opportunity for girls to get introduced to a variety of fields quickly: materials science, mechanical engineering, computer programming, electrical engineering. Railey believes that a little familiarity with engineering concepts can foster both confidence and curiosity. The girls themselves see that working collaboratively on projects can lead to tangible accomplishments. And they get to know some successful and enthusiastic female engineers.

Open Sharing, Take 2

An MIT graduate who works on oceanic robots at the MIT Lincoln Laboratory, Railey is also a believer in open sharing. Last year she published Girls Who Build: Make Your Own Wearables Workshop, an OCW site that shows how girls make jewelry with a 3-D printer, laser-cut materials to assemble a purse, and program LEDs so they light up on shoes they wear.

Now OCW has published a second Railey workshop, Girls Who Build Cameras. The OCW site has a rich array of resources, notably video lectures on digital cameras, the applications of camera technology, and image processing by coding Instagram-like filters. The site also has lecture slides, an image gallery of workshop activities, instructions for those activities, and supporting files. There are also video presentations by women from the MIT Women’s Technology Program and the Society of Women Engineers.

Inspiring Role Models

The guest lecturers are young, mostly female engineers doing exciting work in their careers, such as medical imaging, satellite and space imaging, and sophisticated image processing.  They show that the same technology that we all have at our fingertips in our cell phone cameras has amazingly broad applications, from revealing the ins and outs of hazardous places to sharpening the murky photos of a shipwreck.

Railey also includes on the OCW site some handy resources for instructors who want to host their own workshops, such as a video of the opening minutes of Cameras and a promotional video explaining the Girls Who Build concept.

Railey has definitely found a successful way to introduce engineering and coding to high school girls, some of whom may never have considered these fields before. By using topics of interest like wearables and Instagram, Girls Who Build demonstrates how much fun learning and teaching coding, engineering, and science can be.

Making the Past Present with Hands-on Humanities

PHoto of several people around a wooden workbench.

Professor Jeffrey Ravel and students work on building a printing press. (Photo by Jonathan Sachs / Jonathan Sachs Graphics, Inc.)

By Joe Pickett, OCW Publication Director

MIT is famous for its hands-on engineering projects that students work on into the wee hours of the night. There are over 40 maker spaces at MIT, where students can design and build to their hearts’ content. During their undergraduate years, students assemble a huge variety of vehicles and devices, from aircraft to ovens, and they make models myriad and sundry.

And it’s not just in engineering classes where these creative energies play out.

Case in point: OCW has just published 21H.343J Making Books: The Renaissance and Today. Taught by Professors Anne McCants and Jeffrey Ravel in Spring 2016, the course has three centers of activity: 1) a review of the history of books in Europe from about 1450, when printing was introduced, to the French Revolution, 2) an examination of books made during this period in MIT’s Libraries and the MIT Museum, and 3) the construction of “a functioning, durable printing press based on Early Modern European designs.”

Appreciating the Innovations of the Past

Photo of a wooden printing press in a workshop.

The completed printing press. (Photo by Jeffrey Ravel.)

That’s right. Students built a printing press from scratch, based on Early Modern European designs, under the guidance of Ken Stone, long-time director of the MIT Hobby Shop. Read the complete story of how they created the press from a single, huge wooden beam in the article Mens et Manus in the History Workshop, and this accompanying video:


For good measure, the students also made paper from pulped rags.

“One of the values of making something that seems prosaic, especially something that is now as common as paper, is learning that we moderns are not the only clever ones. People in the past were clever too, and they also knew some things we don’t,” observes Professor McCants.

The OCW site has lecture slides and an image gallery in addition to a list of readings and videos.

Insights about Teaching Hands-on Humanities

In their Instructor Insights on their This Course at MIT page, McCants and Ravel explain how they developed the course, used archival materials, assessed the students in their hands-on endeavors, and incorporated an online forum. There are also reflections from students on their experience discovering the past and making it present.

Anyone interested in exploring further the subject of the “print revolution” and its possible parallels to our own digital revolution would be well-served by visiting Professor Ravel’s 21H.418 From Print to Digital: Technologies of the Word, 1450 ̶ Present.

Math That Can Take You Higher

Two versions of a circular diagram, with a small round object in the center and a pattern of waves wrapping to the right. Upper image is a grid of lines with varying density; lower image renders this density pattern in smooth colors.

An adaptive grid (top) used to compute the supersonic flow around a cylinder (Mach number = 2). The methods taught in this class form the foundations for computational fluid dynamic analyses such as this. (Image courtesy of Prof. David Darmofal. Used with permission.)

By Joe Pickett, OCW Publication Director

Airliners crisscrossing the globe, rockets hurtling into space, satellites orbiting distant planets—it’s where the fantastic meets the familiar—it’s aerospace! It’s where dreams of soaring above the clouds come true. And those dreams are made real by—mathematical models!

The methods underpinning those models are the focus of 16.90 Computational Methods in Aerospace Engineering, a course just published on OCW.

The OCW site showcases the materials for this course as it was taught in Spring 2014 by Professors Karen Willcox and Qiqi Wang. To improve student learning, the instructors used the Residential MITx platform to flip their classroom, requiring students to work through the assigned readings and problem sets before coming to class, so that class time could be devoted to problem-solving, small group exercises, and project work.

Learning Units, Measurable Outcomes, and Content Types

The course site is arranged in three main learning units, each with readings and simple, interactive assessments that allow students to test their understanding. The reading materials and assessments in each unit are linked to measurable outcomes, the skills that students are expected to demonstrate to pass the course. Thus, students can easily identify exactly what they are supposed to get out of a given session in the course, and they can immediately find the resources necessary to master that very topic.

The site also features many lecture videos, lecture notes, and homework assignments—these resources are assembled together by content type (rather than linearly) for user convenience. As the course was running, the lecture videos were broadcast live over WebEx so as to allow students to engage in remote activities, such as presenting at conferences, without falling behind.

Three programming projects were required in Spring 2014, and descriptions of these projects, along with sample student projects, are also included on the site.

What Happens When You Flip

Professor Willcox discusses the challenges of teaching a flipped classroom in her Instructor Insights on her This Course at MIT page, and the challenges were considerable. Creating the online materials, such as the class notes and the assessments, took a lot of thought and effort.  When you’re used to standing at the front of a lecture hall and taking the students where you want to go, it can be unsettling to find yourself winging it. It takes some getting used to:

“I was used to going into a classroom and delivering a great blackboard lecture on a particular topic. I learned it can be overwhelming to walk into a classroom and not know how exactly how the session will go because it will depend on how well students grasped the material they read on their own. This took some getting used to. It’s harder to plan for these types of sessions. You have to be willing to be flexible, and you need to be prepared to facilitate the session in several different ways depending on students’ learning needs.”

Professor Willcox also discusses what led her to create the measurable outcomes, why she prefers giving oral exams, how the programming projects get students to apply their skills to real problems, and the advantages of co-teaching the course.

Connections that Give Students More Control

A long-standing champion of OCW, Professor Willcox is one of MIT’s leading educational innovators. She is a main force behind MIT Crosslinks, a project that links topics in the MIT curriculum to online educational resources (including but not limited to OCW). Among her other educational initiatives is the MIT Undergraduate Curriculum Map, which shows the relations between subjects in the MIT undergraduate curriculum as well as which of these subjects have been published on OCW.

And (as if all this weren’t all) Professor Willcox is piloting Fly-by-Wire, a blended learning technology to help at-risk students in secondary schools stick with their studies and apply themselves, so they can graduate and take off.

Eight new OCW courses in October

Photo of a rock, crumpled up paper, and scissors.

The well-known hand game Rock, Paper, Scissors is an example of what game theorists call a strategic interaction, as discussed in the new OCW course 14.16 Strategy and Information. (Image courtesy of Jesse Kruger on Flickr. License: CC BY-NC.)

OCW is pleased to highlight these courses published during the month of October. Five courses are brand-new subjects on OCW, and three courses are updates of older versions.

New Courses

Updated Courses

Person-to-Person in Urban Sociology

Photo of urban street scene, with brightly painted front of an auto muffler shop.

A neighborhood in the Bronx, New York City. Part of this course focuses on the changing concept of “community” and the effects of neighborhood characteristics on individuals. (Courtesy of Axel Drainville on Flickr. CC BY-NC.)

By Joe Pickett, OCW Publication Director

Teaching at the college level is often exciting and rewarding, but it is rarely easy, especially in discussion-based classes, where learning depends on student participation. Getting shy students to share their opinions in a classroom, and preventing the extroverts from dominating the conversation—these are perennial challenges for instructors. Students can have very different backgrounds, with different notions of forwardness and politeness, so establishing a civil dialogue can be a delicate matter.

That’s assuming the class is taking place on a college campus. How much more difficult would teaching be in a prison, with half the students as inmates and the other half as young eager beavers from a celebrated nearby college?

Professor Justin Steil and Teaching Assistant Aditi Mehta took on this challenge as instructors of 11.469 Urban Sociology in Theory and Practice, newly published on OCW. In Spring 2016 they taught this course at the Massachusetts Correctional Facility in Norfolk, MA, where about half the students were inmates participating in the Boston University Metropolitan College Prison Education Program.  In their Instructor Insights on their This Course at MIT page, Steil and Mehta explain their strategies for breaking the ice between these MIT and BU students to create a collaborative learning environment.

Opening Up Discussion through Collaborative Assignments

One way to get people talking is to have at least one student from each group working together on assignments.  The task can be simple, such as handing out to each group identical images of urban life, and then having the students with matching images join up and generate some observations about what they see.  Other assignments, such as presentations on the Spring 2016 readings, required similar cross-group collaboration. The challenge for the students was compounded by the fact that they could not communicate outside of class because of prison rules. That meant that all of their presentation’s insights and structure had to be developed during class breaks.

In this environment, discussions bloomed and interestingly showed some telling differences between groups. The MIT students tended to focus on “the oppressive power of larger socio-economic structures,” while the BU students felt that this viewpoint was too limiting and “found more dignity in recognizing the significance of personal choice and agency.” As the instructors saw it, “The micro ‘personal stories’ and macro ‘abstract analysis’ were different and valuable ways of making sense of and engaging the same material.”

Unleashing the Power of Low Tech

The BU students had no access to the Internet, email, word processing, or printers, so Steil and Mehta had to prepare everything in paper form before class. This forced them to be more organized than they would otherwise have been. They believe that it improved the dynamics of the class as well:

“Simply making eye contact with someone when they speak instead of typing on your computer actually builds trust.  Students were really listening to each other, and distractions were not a problem in this class.  And as instructors, lecturing or teaching without A/V aids forced us to internalize and embrace the material and communicate it clearly. We could not hide behind a pretty slide or bullet points. In our future teaching, we hope to continue embracing this way of facilitating and learning— simply person to person.”

It’s Only Logical to Take This Math

Image of a 4x4 square puzzle with different numbers in each square, one square empty, and spelling out the course number 6 (blank) 4 2 on the diagonal.,

6.042 serves as an introduction to discrete mathematics, probability, and mathematical thinking for computer scientists. (Image by OpenCourseWare, based on an image by Nick Matsakis.)

By Joe Pickett, OCW Publication Director

If you’re interested in computer programming, you might be familiar with OCW’s extensive resources in the discipline, ranging from our introductory classes to the graduate courses offered by the Department of Electrical Engineering and Computer Science.

Sooner or later, students must face the reality that to do serious programming, design algorithms, or become a software engineer, they need to know some math.

What kind of math?

The kind presented in 6.042J Mathematics for Computer Science, whose Spring 2015 course has just been published on OCW. Taught by Professors Albert Meyer and Adam Chlipala, the course has an extensive array of content covering a wide variety of mathematical topics. 

Tutorials, Textbook, and Much More

Chief among these resources are 130 short tutorial videos created by Professor Meyer, who drew on more than a decade of teaching experience in the subject to create them. Ever an educational innovator, and one of the first instructors to flip his classroom at MIT, Professor Meyer put his Spring 2015 course content on Residential MITx, MIT’s version of the Open edX platform. MIT students watched the videos via the online platform before coming to class, where they worked in teams to solve problems.

Screengrabs of video player, with interactive text transcript below, and interactive questions, with horizontal navigation bar above.

A sequence of two OCW pages from 6.042J. Left: Tutorial video, with interactive text transcript. Right: A pair of interactive questions that come after the video.

Now on OCW, the video tutorials are presented in the same sequential fashion, interspersed with brief interactive questions that allow you to check your understanding, over four learning units.

The in-class questions are also included on the course site, in a table showing the relevant video tutorial for each one, so you can get the same background that MIT students had when they were asked to face these challenges.

The entire course textbook is also available for free and can be downloaded.

All the non-video resources for the course are gathered together in a handy course index, so you can see in one place which resource aligns with which for each week of the semester, including the problem sets and exams.

Other Versions, Other Resources

The Spring 2015 course site is but the latest version of 6.042J to be published on OCW. Math enthusiasts can find more excitement in a Fall 2010 version taught by Professor Tom Leighton and Dr. Marten van Dijk (which features full video lectures), and a Fall 2005 version, co-taught by Professor Meyer and Professor Ronitt Rubenfield, that has solutions for its in-class problems, problem sets, and exams.

It all adds up to a very logical conclusion: OCW’s suite of 6.042J course sites is awesome!