Empirical evidence has been provided about the importance of avoiding American Psychological Association (APA) errors in the abstract, body, reference list, and table sections of empirical research articles. Specifically, authors are significantly more likely to have their manuscripts rejected for publication if they commit numerous APA violations--and, thus, do not write with discipline--in these sections. In addition to adhering to APA, writing with discipline also includes avoiding what I call "formal grammatical errors." Thus, in this study, I analyzed formal grammatical errors committed in 117 manuscripts submitted to the journal "Research in the Schools" over a 6-year period. Among other results, I identified the 35 most common formal grammatical errors. The use of colloquial words/phrases (e.g., "the author did a good job") (76.1%) represented the most common grammatical error. Further, I identified a link between the number of grammatical errors and the subsequent disposition of a manuscript (i.e., accept vs. revise and resubmit vs. reject). Finally, I identified the formal grammatical errors that best predicted whether or not a manuscript was rejected by the editor. I contend that an efficient way for authors to learn how to write with discipline is to focus initially on these most common formal grammatical errors. Further, I contend that these errors provide useful starting points for persons who teach scholarly writing. Finally, authors of the APA Publication Manual might use this information to determine which grammatical rules and guidelines to emphasize.