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Document Version: 1.1
Last Modified: 2009.04.28

Please see the terms page for an explanation of technical terms used below. Developers may also wish to read the basics page for a list of features and approaches recommended for flashcard applications.

There are a number of issues that repeatedly come up in the course of my reviews of flashcard software. I have decided to compile some of the problems and issues and my positions on them below for easy reference.

Interface Issues

The Flip Fixation Flaw

A flashcard application is said to be guilty of the Flip Fixation Flaw when the developer’s attempt to emulate the experience of studying and flipping a physical flashcard comes at the cost to the student of time or software functionality.

In principle, there is nothing wrong with creating a digital flashcard experience within educational software which is modeled upon the original physical paper based flashcard. This only becomes a problem when the marginal benefit of this approach is outweighed by the cost in terms of speed, space, and visual experience.

It’s Not Just about the Flipping

The three most common ways developers commit the flip fixation flaw are:

Lost Speed – When there is a non-trivial amount of time wasted upon creating the visual experience of “flipping” a digital flashcard to show another side of the card or sweep the card off the screen to show the next card. Because reviewing a well-studied flashcard can take less than a second, anything but the fastest flip animations can easily double the time it takes for a student to study a medium to high volume of flashcards.

If developers really want to flip the cards, then please: flip’em really fast!

Lost Space – In order to further give the user the impression they are looking at a physical card, developers often draw an image of a rounded or regular rectangle on the screen in which the content of the card is displayed and upon which the flip action is performed. This is a terrible waste of screen real estate because both the card and sometimes dozens of precious pixels are being wasted that might have been better put to slave labor portraying bigger fonts or more text.

Even if you want to “flip” the digital flashcard, we don’t need to waste screen space on a cute little flashcard, just flip the whole screen or canvas on the window.

Lost Memories – Some developers, who apparently really miss the real thing, like to create flashcards which reproduce the red vertical line and blue horizontal lines on ancient paper flaschards and elementary school notebooks.

Get over it, move on! Are you worried the users are going to type out of line or off the left margin? It may spark moments of nostalgia for people like myself who have actually used the brand of physical flashcards that looked like this, but no, we really don’t want to stare at the blue and red lines when we practice our flashcards.

Interval Study Issues

The Cookie Monster Flaw

In the memorable words of a failed Sesame Student, “Me not continually review cookies at increasingly spaced intervals, me eat the cookie.” This flaw is, of course, exhibited by any flashcard software which offers no interval study but it is included here because it is also a problem with some approaches of applications which actually do support interval study: If an interval study system offers a finite number of interval stages, at which point the interval study for a given unit of information is said to be completed, it is guilty of the Cookie Monster Flaw.

The idea for this comes from the practice, prevalent among some students in places such as China, Korea and Japan, of learning vocabulary directly from a dictionary. In an ritual act of symbolism, once all the words, or chosen words, from a given page of a dictionary have been “memorized” the page is ripped out of the dictionary and consumed. My experience, admittedly not backed by evidence from a full empirical study, suggests that thus physically digesting the ink and highlighter fluid of memorized words does not in fact have much of an impact on long-term retention of vocabulary.

Developers should keep this principle in mind:

Even native speakers forget their own languages during extended periods of disuse; no interval study system should be designed in such a way that implies the complete and final memorization of any unit of information.

The Insatiability Flaw

The insatiability flaw is exhibited by flashcard applications which provide no pause or “completion” during the course of interval study in such a way that recognizes that some cards are not currently in need of review. It is problematic because it provides users with no way to efficiently manage their time by endlessly prompting them to review cards which the student is not likely to be on the verge of forgetting.  Obviously, they can and should be continually prompted if there are indeed words that are untested or which are due for review, but otherwise, the application shouldn’t drag out cards that need not be reviewed for weeks or months (Though they should provide a way for users truly eager to continue reviewing, or offer a comprehensive study on demand feature).

Students turn to flashcards because they believe their study is a useful and efficient form of study. Most of them recognize that, when it comes to vocabulary acquisition and maintenance for example, it is an inferior method when compared to the frequent and sustained production and practice of a language in an organic communication setting. However, given that we do not always find ourself in such a setting, or find the range of our communication more limited than that needed for reaching and preserving our desired level of proficiency, flashcard study is an imperfect but helpful alternative.

However, given that our time is a limited resource and we may be engaged in flashcard study of multiple languages or sets of knowledge units generally defined, flashcard applications which are “insatiable” in their appetite to prompt us to review words give us no indication of when we have completely reviewed all words we are on the verge of forgetting. 

The best way for a developer to think about this when designing their application is to remember that while it is crucial that the developer avoid the more serious Cookie Monster Flaw they should also keep this principle in mind:

An interval study system nears perfection the further it approaches an environment which only prompts a student to review those units of knowledge they are on the verge of forgetting.

If there is some advanced algorithm included which takes into account the user’s truancy it may want to provide early prompting of words that are not quite yet on the verge, but only based on some statistically guided expectation of future truancy of the user.