Scenario
Joe is a student taking Japanese 2 at MIT. The class uses the Genki 1 textbook, and has studied the grammar, characters, and vocabulary up to Chapter 10. The textbook has taught Joe some useful grammar and vocabulary, but not enough to read most of the Japanese-language content on the web or in books. The textbook contains some example sentences for reading practice, but Joe has already read them and still doesn't feel like he's mastered the material. Joe want to practice reading additional sentences to solidify his understanding of the grammar, characters, and vocabulary that have been taught in Genki 1 up to Chapter 10.
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This design has very little state - the type of grammatical structures and vocabulary that the user is expected to understand are listed in the left sidebar, and this dictates the sentences that will be displayed to the user. While information about the sentence's vocabulary, grammar, romanization, and translation are hidden in the accordion menu by default, this is by design, because it is meant to be relied on only if the user has trouble reading the sentence without assistance.
Error
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Prevention
The usage of opening a new tab for displaying additional sentences when the user clicks the "more sentences" button in the Vocab or Grammar accordian menus, instead of modifying the state of the current tab, is chosen so that it is easily undoable - the user can simply close the newly opened tab to return to the original sentences he was looking at prior to clicking the button.
The editing functions - namely, adding and removing grammatical tags from sentences, and changing translations for sentences, are unfortunately not undoable. For this reason, because this model functions much like a wiki - in that any user is able to edit or contribute any sentence - it may be necessary to introduce some form of history into the interface should accidental editing or vandalism become a problem.
Design 2
Storyboard
This design provides the student user with a ‘home’ view (Figure 2) of all the textbooks that he is learning from. A user can add and search textbooks from any page by using the ‘Add/Search’ bar labeled in Figure 2. The user can either search for a title (Figure 4), or see an alphabetical sorting of all the textbooks in the system (Figure 3). Also, there are language filters along the right to allow the user to narrow his search. After the student has added the book to his textbooks, he can return to his ‘home’ via the ‘My Home’ link that is located at the top of every page and then pick a book from his selections.
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Other features demonstrated in Figure 6 include the ‘Look Up’ feature that lets the user filter the accordion-style listing of the words in the current chapter. If the user wants to practice the vocabulary in this chapter, he clicks the ‘Practice’ button, and the system will switch to a flashcard like interface (Figure 7). The user can mark a card as correct or wrong to indicate whether he has mastered the sentence. Additional options are ‘Previous’, ‘Show Answer’, ‘More Like This’, and ‘Next’. The ‘Previous’ option lets a user backtrack to the previous word that he practiced.
Learnability: 
Usability Analysis
Learnability
Pros:
The user interface has many affordances. A plus sign is used for adding a book (Figure 3 shows this) to your collection, a minus sign for removing (Figure 2), and a ‘return’ arrow for restoring a removed book (Figure 2).
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The ‘Add/Search’ bar has an auto-complete feature to assist users in entering a title. This helps users who cannot remember a title completely.
Cons:
The procedure to add a new sentence is not very obvious to the user. In order to add a sentence, the user must list all the words (Figure 6; he may also use the look up feature) and select the vocabulary word for which he wants to add a sentence. This feature is visible only to users who have privileges, so novices cannot learn this feature until after they have mastered a part of the language and have acquired privileges.
Visibility
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Pros:
The state of the system is visible to the user. In Figure 7, the current title is displayed in large text alongside a picture of the book’s cover to remind the user what book he is currently looking in. Along the left hand side of the interface, the selected chapter is highlight and boxed to indicate which chapter is being studied.
Cons:
The visibility of a user’s mastery of each word or section is not displayed unless the user explicitly lists all the words (Figure 6). Thus, an unaware user might feel that he needs to keep practicing sentences from a particular chapter even though he might have a high mastery rating for all the vocabulary in that chapter.
Efficiency
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Pros:
The following items are in the same location on every page when logged in: ‘My Home’ button, ‘Add/Search’ bar, Logout button. Thus performing these tasks is easy from every page.
Cons:
Performing a search for a book can take a long time. Although there is a language filter and alphabetical sorting of the books, the user must still linearly scan through the items. If there are many books, the filter and alphabetical sorting are not enough.
Searching for a word in a chapter (Figure 6) can be tedious and time-expensive task if there are many words in the chapter. The interface attempts to counter this negative effect by providing a word look-up search bar to narrow the search.
Error prevention
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Pros:
A user may make changes to his collection of textbooks including removal of unused textbooks and addition of new ones. If a user accidentally removes a textbook from his ‘home’ view, he has the option of returning it to his collections. That is, permanent removal is a delayed process (shown in Figure 2 by the ‘Time Until Deletion’).
The ‘Log Out’ button is located in a corner away from other features of the interface. This prevents the user from accidentally logging out.
Cons:
If a user has many textbooks, the removed textbooks are pushed down and out of the user’s locus of attention (Figure 2). A user who is unaware of a removed textbook might never learn of the book’s removal until after its deletion because the removed textbooks are located out of sight.