Why is CS taught to be memorized?

Question

I have been taking Advanced Placement Computer Science for this past year in high school. It seems as though we are taught simply to memorize code and functions and not how to be resourceful and efficient in using documentation and the like.

Practically, I imagine many (if not all) programming jobs would allow you to flip through documentation, review past code and the code of others, essentially doing what my teacher would consider "cheating."

While I do agree core concepts are essential to memorize (in any subject matter), it seems superfluous and impractical to me to give a pen-and-paper exam for a CS class, especially when practically you would have a compiler, debugger, reference manuals, and the entire internet to refer to in any real-world work situation.

Why is CS taught focusing on the memorization of code and functions as opposed to teaching useful skills including how to use and interpret documentation, sample code, the debugger and such?

Answer 1

In a high school class, you're in the most basic level of your path to mastery. Things that are covered in your class are the kind of things that a professional programmer are expected to know cold. In a lot of ways, this is akin to learning your "times tables". Of course you'll always be able to grab a calculator in a "real-world" setting, but this memorization not only increases your speed in more complex tasks, but also promotes a more thorough understanding of the basic principles.

For example, you should know several sorting algorithms, how they're implemented, how they work, when they're best used, and when not to use them. This could always be looked up, but shouldn't have to be - anymore than a mathematician should have to look up 6 times 8.

Answer 2

It is often taught this way because teachers generally don't know any other way of testing understanding. Your feelings are completely correct in that it is worthless to be taught like this. The way people are educated in general is in need for reform desperately!

Life gets better though, at least at UIUC I have found that the higher you go in your CS classes the less the exams are oriented as you are describing and in the majority of my courses we have been allowed a cheat sheet for the all the crap that you would likely have googled if you were actually sitting at a computer.

That being said, the higher up I have gone in my classes the less they actually teach you about languages or how to implement something. In fact I have only had one class where they have actually taught us anything about programming, it's mostly been abstract mathematical concepts and we have been expected to just figure out the programming part on our own (provided they were always happy to help but this was never something on an exam).

Answer 3

Don't let schooling interfere with your education.

-- Mark Twain

I'm a mexican and telling you this because in Mexico is not exactly a good place for education (in any level), at least in public education.

Well, at the middle of my career (CS) I feel exact the same way you're feeling, so I start learning by my own and I spend one year learning algorithms, linux, scripting, how my computer works, a bit of relational databases, html, css, etc (a little about all). And of course, I had to skip classes*, let my grades down* and graduate one year after*, all in order to learn.

After that year, I return to my "normal" routine, back to regular classes, homework, exams and projects. The classes were still boring, nothing new to learn, all was the same. So I decided to enter to programming contest sites like UVA judge online, code chef and project euler, then I watched some lectures at the MIT Open Course Ware and I was still learning by own, but in a different way.

The lesson: Don't let the things happen, make the things happen. If you're not happy with the way you're learning, change It!

*Not the wisest decisions that I have made.

Answer 4

It depends on what you are trying to memorize...

In order to study math, for example, you have to be familiar with algebra and you frequently have to be rather creative in how you go about performing algebraic manipulations in order to simplify equations. But you have to have memorized certain building blocks in order to be able to focus on those interesting bits. You have to, for example, know your multiplication tables by heart and you have to know some identities so that you can recognize how to manipulate the equations in order to use those identities.

In order to study computer science, you similarly need to be familiar with basic building block data structures and algorithms because you're going to need to apply them to higher level problems. It's highly unlikely that you'd ever, for example, write your own linked list implementation in the real world, you'd simply use the one provided by your library. But knowing how a linked list is implemented and how to implement your own, you'd be able to reason about where and whether to use a linked list when you start working on higher-level problems. Similarly, you'd never write your own binary search function but it's important to understand how it works so that you can reason about things like where a database could use an index and where it couldn't.

Once you have some basic building blocks memorized, it's much easier to do things like interpret documentation. Documentation might indicate that a list is being used and assume that the programmer implicitly knows that this means that inserts are O(1) and searches are O(n). The building blocks are also vastly more stable over time-- you're very likely to use new debuggers every few years, you're likely to use the same binary search your entire career.

Answer 5

"Why is CS taught focusing on the memorization ... as opposed to teaching useful skills" - I think you are discounting memorization a bit too much. Just as you should practice writing code, interpreting documentation, using debugger, you should also practice memorization.

You may be surprised how much more efficient you can become if you don't have to go to API reference as often or look up as many debugger commands.

One of the best things I learned in highschool was by observing a friend who never took any notes in class. His argument was that he could remember what's important. I started doing the same thing and do think that it improved my memorization skills which I find very useful on daily basis even with all those API references handily available.

Answer 6

Pen and paper exams actually do make sense if the goal is to test a complete understanding of the subject at hand. I did take the Computer Science AB exam almost a decade ago and I agree with the pen and paper method.

You should know enough of any algorithm you learn in the lower levels of Computer Science to be able to reason out how to write the implementation code in your target language. Students should also be able to write code by hand with mostly correct syntax. We all miss a semicolon or parenthesis sometimes :). Also debugging and design skills can be tested without inference from a helpful IDE.

If a student cannot do this, then they do not possess mastery of that topic, just perhaps a passing familiarity.

Answer 7

In my experience, memorization comes with simple practice and there's absolutely no need to teach it at all. More importantly, this approach means only memorizing what you actually need to remember in whatever you're doing, not a bunch of random junk that your teacher hopes you might need and invariably you won't. The time spent memorizing the implementation of some algorithm could be much better devoted to some other cause.

After all, why would you ever need to practice writing an algorithm? Once you write it once, you can re-use it for all time- even on the exceedingly remote chance that someone else hasn't already written a freely available implementation for the language of your choice and that your environment doesn't already provide such an algorithm for your use, which is trivially not true for the vast majority of simple algorithms like sorting and such. Practicing something where it's highly unlikely that you'll ever have to do it in the first place and even if you do you'll only ever have to do it once? Not a valuable use of time.

The important thing to know about Heapsort is not how to implement it at all. It's the operating complexity in best and worst cases, and similar things. But, surprise, there's a handy-dandy table on Wikipedia that will instantly give you this information. So again, there's no value in having that knowledge. It's instantly available for you whenever you want it from now until the end of time at effectively no cost. So why would you want to memorize it? It's pointless.

In my experience, there is absolutely no reason to require a student to memorize anything. If you're asking a question which can be answered from a reference source, then you're asking a question where being able to answer it has no value.