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The paper prototyping stage helped us establish our initial risk assessments - namely, that the main difficulty was conveying to the user our model that sentences would be displayed only if the words they contained were specified as being displayable in sentences, and included the study focus if there was one. Thus, we focused our prototyping efforts mainly on the vocab and textbook selection, and less on reading and understanding the sentences themselves or contributing sentences, with which users had little difficulty in prototyping stages.
One of the critical decisions we made early in the design process was our model for which sentences would be itself, which we thankfully ended up revising to be more lenient after prototyping. Namely, initially we would not display sentences if they didn't have words that the user had selected as being allowed to be displayed; later we would allow sentences containing words the user hadn't selected as being allowed to be displayed.
After we implemented the computer prototype, our basic design layout stayed the same for the most part. Although, we did discuss alternatives that we ultimately discarded upon realizing that the ideas would clutter the screen or be inconsistent. For example, we discussed using a tree view to display words in the word look-up in the left side bar, but decided that tree views were mostly associated with outlining information rather than displaying information. Looking back, we realize that we should have paid more attention to and experimented more with the wording used in the interface. The problem was apparent from paper prototyping, but we had thought the problem was sufficiently addressed in computer prototyping. However, the problem surfaced again in later stages due to insufficient tests.
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