Sentence fragments, comma splices and run-on sentences are among the most common middle school student writing mistakes. A sentence fragment is an incomplete sentence, one that is missing either its subject or its verb and does not contain a complete thought. "The fluffy white dog with the squished nose," is a fragment.
Run-on sentences, also called fused sentences, combine multiple sentences into one single string without conjunctions, or connectors, and without proper punctuation. "The girl went to the store she saw her friend they went to the mall" is a run-on sentence.
Comma splices often occur when the student realizes that something is wrong but isn't sure exactly what the problem might be, so he sprinkles commas into the word chain. For example, "The sky was dark, it was starting to rain" is a comma splice that tries to join two sentences with a comma instead of using a semicolon or conjunction, or by making two sentences.
A simple check for all of these errors is to underline the subject and verb again, making sure that both are present and that, if the sentence has more than one of each, it also has a conjunction.
Middle school students often fail to focus a paragraph on a single idea. A student might, for example, begin by describing her visit to her grandmother's home and then veer into a description of an elderly woman she saw at the movie theater, all in the same paragraph. To identify this, have your writer underline the topic sentence and then cross out any sentences or phrases that don't relate directly to that sentence.
Homonyms also seem to trip middle school writers, who may be confused about the use of like-sounding words like "their," "there" and "they're." The best solution for this problem is practice, so encouraging your student to compose thank you notes and other writing regularly may help.
Other common mistakes in this area include subject-verb agreement. Pronoun-antecedent agreement, such as "Each dog eats their bone," instead of "Each dog eats its bone," also bewilders middle-grade writers at times. Misplaced modifiers can turn a serious sentence into a comedic one-liner, as well. Reminding students to keep modifiers as close as possible to what they are describing will help prevent sentences such as "Eagerly awaiting the train, Joe's suitcases were lined up on the platform," which makes it sound like the suitcases are excited about traveling.
Misspellings and incorrect punctuation are also sweeping in the writing of many middle school students. Writers can check end punctuation by asking themselves whether a sentence is giving information, thus requiring a period, or asking for information, which needs a question mark. Reading the paper from the last word on the right side of the page, back across to the left and up the page helps you see what is really on the page instead of what you expect, which helps catch commonly misspelled words.