I was wondering if it would be possible to request the addition of practice exercises that incorporate the diagramming of sentences. The students could start by dragging and dropping the parts of speech onto a line to label each part of speech in the sentence. Then, they could write the part of speech to label each word in the sentence. This would force them to think about the parts of speech more. Also, they could be asked to notice where in the sentence cirtain nouns were, to notice the verb, which is usually in the middle. There could be questions like "Where was this noun located in the sentence? Was it in the beginning, middle, or at the end? Then it could move from the parts of speech to labeling the subject, predicate, direct object, etc. Showing how those are beginning with each part of speech and where they are in the sentence. There could be questions like: "Where is the subject of this sentence located?" This will help build their awareness of the placement of different parts of speech. Another type of useful activity is correcting the paragraph. You already have them in the program, but the students need a lot more of those practices. They need to consistently practice fixing punctuation: When to capitalize; where to place commas, periods, question marks, quotes, exclamation points, etc. When to italicize or use quotes for titles of cited works. Another thing that would be helpful is something to teach them formatting for academic writing, such as MLA style and APA style. I realize that isn't necessarily grammar, but it could be an extension on lessons like the ones in Quill for more advanced classes.
