Category Archives: Education

The Digital Textbook

The reason many developers become involved in open source projects is to “scratch an itch”, to fix a problem they are having with some software (or lack of existing software) when trying to accomplish something. Wikipedia works in much the same way, readers who see problems, omissions or errors (at least in theory) become editors fixing the problems. In general this works pretty well in terms of producing excellent output which meets the needs of the community, at least those contributing.

Textbooks have long been the domain of publishers and authors contracted by those publishers. K-12 textbooks especially have been notoriously inaccurate and out of date when it comes to sciences and technology. I think that openly licensed digital textbooks are set to change that. Much of the outdated information comes from the long lead time for traditional textbook editing and printing. When inaccurate information is found it is often either too late to do anything about it or the person finding it does not know who to contact to get the error corrected (or the person they contact can’t or won’t do anything about it).

The advantage of an openly licensed textbook is that any teacher or researcher who finds an error can correct it and republish the updated book. These “patches” can either be integrated upstream or “forked” in much the same way as is done with open source code. We certainly want schools and teachers using these textbooks to vet them prior to implementing them in the classroom, but this is not a problem with the model itself, it is just a shift from trusting the publisher to vet the textbook (was that ever a good idea anyway?) to trusting the school or district to do it. In some cases it may make sense to have some experts “certify” versions of the textbook as accurate as well. These certifications might also provide some kind of revenue model.

In addition, the fact that digital textbooks can be easily corrected and re-distributed or updated as new technologies emerge and discoveries are made helps keep information up-to date and as accurate as possible. Don’t get me wrong I think it will still be quite a number of years before schools are replacing all their textbooks, but the cost savings and advantages are significant so I suspect it will begin to happen sooner rather than later.

Two websites which are helping to move things in this direction and which are providing some digital textbooks to schools now are the California Learning Resources Network Free Digital Textbook Initiative and CK-12 Foundation.

There’s more than Chernobyl and Three Mile Island

One of the classes I teach at the University of Minnesota is a course on Technology and Public Ethics. In this class we attempt to uncover some of the social and ethical issues surrounding technology. In some cases technology is a solution to a social dilemma and in other cases it creates or contributes to the dilemma. One topic we look at is the production, transmission and consumption of energy. In the study of society and ethics cut and dried answers are few and far between, such is the case for nuclear power.

While nuclear power has traditionally been viewed with disdain because of a lack of understanding about how it works, the dangers involved and the question of nuclear waste it is again being discussed as a power production option as we become more concerned with the causes and effects of global warming, specifically carbon emissions such as those from traditional power generation sources. In the end nuclear power may provide an important supplement to renewable energy sources in combating the problem of carbon emissions. Before arriving at a conclusion like that it would be important to understand concerns surrounding nuclear power. For the most part these center on the potential for disasters and nuclear waste. While many people have heard of the Three Mile Island incident in the United States and the Chernobyl incident in the Ukraine (see this posting) these are certainly not the only incidents on record.

Two incidents that took place much earlier in the history of nuclear reactors were the Windscale (U.K.) and SL-1 (U.S.) incidents. Thanks to the web you can read about these incidents from several sources:

In addition to these reactor incidents there have been many incidents or close calls in research laboratories which, while they do not generally pose a significant threat to the general public, are dangerous for those in the immediate vicinity.

There is also the question of what to do with nuclear waste. One might argue that a sound policy is the reprocessing of nuclear waste into less harmful and more useful/reusable isotopes and while this has been met with success in Europe it is not currently policy or procedure in the United States where indefinite storage is used. The current plan is for waste to be housed deep underground at Department of Energy storage facilities (Yucca Mountain and WIPP). One of the challenges posed by this plan is a desire to warn future generations of the potential hazards in these locations when all current languages might be lost. This article explains some of the proposed solutions for just this problem.

DIY Rapid Prototyper

Those familiar with rapid prototyping (essentially 3D printers for computers) know that both machines and supplies can be extremely expensive. Now a group known as Fab@Home has published instructions and software for building your own rapid prototyping machine. The machine they propose is certainly not as durable or precise as the commercial offerings, but at a fraction of the cost it may serve your needs just fine. If all you’re looking to do is a bit fo experimentation or introducing students to what a rapid prototyper can do a less expensive system such as this might be all you need. NewScientistTech also has a story on the Fab@Home project.

Geeks come in all flavors

Yesterday I happened across “The Power Tool Geek” blog. Written by one of the forces behind an online tool supplier I won’t say it’s not biased towards or against various brands but most people do have a favorite brand of power tool so I won’t hold that against them. Anyway it makes for an interesting read.

On Education and School Reform

There’s been some news recently in school reform circles centered around the opening of the Microsoft “School of the Future” in Philadelphia this fall. One such story is this one at the excellent blog and discussion site of John C. Dvorak. There, in the comments, you can already see the debate among the public-at-large about the effectiveness of school reform measures. This is a common and distrubing trend in talks about school reform. The uneducated public has little knowledge about what makes schools work and what doesn’t. What they have is “feelings” and articles from newspapers and magazines that are often incorrect and unreliable. Anyway, I wrote the following response in an attempt to encourage people to research and understand the problem before complaining and making foolish statements. If you’re interested in this sort of thing a must-read is “The Academic Achievement Challenge” by renowned educator Jeanne S. Chall. I don’t agree with a lot of her conclusions in the book, but it’s a great place to start the discussion.

As someone in the middle of an Education PhD program I have a few things to say. I don’t want to get into a long debate about this because I simply don’t have the time. First, I have read some about these Microsoft schools but I’m no expert. That said, the general public (and the politicians that cater to their wants) knows very little about education. There is a lot (and I mean a lot) of research about how students learn best and the best methods for teaching. The problem with implementation is at least twofold.

First, things like interdisciplinary learning work well, very well in fact. Here the implementation problem is generally cost. To do interdisciplinary learning well teachers of different subjects need to meet on a daily basis for a considerable amount of time and have additional planning time to boot. In effect you reduce the amount teachers can actually spend in front of a class by a quarter, meaning you have to hire more teachers and thus spend more. This is not something that makes the public or politicians happy. If you stary cutting corners to try and do it anyway you end up with less than satisfactory results and no one is happy. I always say that education would be the most expensive thing for the government to provide if it was done right. If people knew how much it really cost to educate someone there would probably be calls for the end of public education and a serious debate about whether education is worth it, it costs that much.

Secondly, public perceptions of education are a barrier to improving it. There is not general public (or political) support to take research into the classroom and apply novel teaching methods. In addition to costing more things like interdisciplinary learning, more teamwork and not having to memorize useless facts and instead learning how to research and solve problems are not what the majority of people want taught in schools. Parents generally are unhappy to learn their child no longer needs to memorize massive amounts of information such as dates and names which can be easily looked up. Even in the comments here you’ll find that people will debate what students should memorize vs. not. The effect is that novel teaching methods are usually undermined and not put fully into place making them less effective. The mentality is often that “I learned all this stuff in school, why aren’t my children” without the realization that there has been a paradigm shift in the world and what was appropriate in the past may no longer be appropriate.

My personal opinion is that people are far too open about criticizing education when they have little knowledge about how the education works. If you’re serious about wanting to make a change in education (or anything else for that matter) and want to criticize it you should spend a copious amount of time studying the research and not the junk you see in the newspapers and magazines, I mean real research studies published in refereed journals. If you start wanting to make changes before you understand why things are the way they are you end up wasting a lot of energy and can potentially cause a lot of students to be ill-prepared for their futures.

Making STEM work with public/private partnerships

Those teachers involved with Technology Education, at least in the United States, are bound to be familiar with the STEM (Scient, Technology, Engineereing & Mathematics) acronym/movement. What you may not know is that the National Science and Technology Partnership (NSTEP) is an education/private partnership designed to create a bridge between educators and electronics companies.

One of their initiatives aimed at Technology Education is called TechXplore which is a research based mentorship and competition designed to improve the science and technology skills of students.

Experiments in backyard ballistics with Mentos and Soda Pop

Perhaps he’s not the first to experiment with it but Steve Spangler has a great deal of information about the now popular (at least with the YouTube and Google Video crowd) sport of creating geysers out of soda pop and mentos on his website. From science teachers looking for an eye-catching and engaging demo for the first day of school to crazy teenagers looking to make “cool stuff” happen in the backyard this experiment is bound to be a crowd pleaser.

Low cost electronics lab equipment

In the past I’ve had good luck purchasing inexpensive elecotronics lab equipment such as autoranging digital multimeters from and would still recommend them but another option has come to my attention. In reviewing some of my literature from the January Consumer Electronics Show (read: working on the backlog of work on my desk) I stubled across the website. To be sure these folks specialize in meters and a few power supplies, not the broader range of equipment that Circuit Specialists has, but if you need to outfit an electronics lab, shop or just yourself with a handy digial multimeter they may be just the ticket.

The Cost of Knowledge

A number of state public interest research groups have created a report entitled “Rip-off 101: Second Edition – How the Publishing Industry’s Practices Needlessly Drive Up Textbook Costs“. If you haven’t spent much time in college classes recently you may not be aware that it’s not unusual for students to spend $900 a year on textbooks. Many students now recoup some of that cost by selling their used textbooks back to the bookstore (let’s not even get into that scandel), but as publishers move towards electronic textbooks that is not going to be a possibility any longer. Of course publishers could drastically reduce the price of electronic textbooks and end up making about the same amount of money but they see this as just another way to profit on the backs of debt-ridden students.

Luckily there has been slow bust steady progress towards free and open “textbooks” and curriculum. This really started with the MIT OpenCourseWare project and has since expanded to numerous other offerings. Of course I’ve already written about Schiller’s free physics textbook, the All About Circuits electronics curriculum and the Learning by Doing CCNA textbooks but now there are even more.

The Textbook Revolution, Free Tech Books and Assayer websites all have lists of different free e-textbooks availible on a variety of subjects. If you’re in the position of influencing textbook purcahsing I would urge you to look and see if any of these free offerings could meet your needs. Perhaps you’ll even blend a few of them to create a free textbook unique to your class. In any event I’m certian students would appreciate the thought.


Subnetting is the art of dividing one network into many by use of a subnet mask. In my experience one of the most difficult things for networking students to master is subnetting. When they need some kind of new viewpoint on the subject I usually send them to This site has been around for several years now and offers free mini-lectures on this important topic. All told there are several hours of video there and you may need to refer to some of the sections multiple times to gain a full understanding of subnetting but it is one of the better sites out there for this.