Teachers can check for plagiarism by watching for uneven style and inconsistent diction choices and then searching for specific or unusual phrases online. MIT Comparative Media Studies and Writing also suggests asking students questions about the essay or research paper in person to see if they can discuss it intelligently. In addition, many plagiarism detection software tools are available.
The University of Maryland developed the Plagiarism Checker, which is easy to use to pinpoint the source of a plagiarized phrase. PlagiarismChecker.com, though it has a similar name, is a different service that does the same thing. Paper Rater is a service that scans students' papers and estimates the probability that the papers were plagiarized; it also does grammar and spelling checks.
Many schools use commercial plagiarism checkers to help teachers. Plagiarism.org sells plagiarism detection software called Turn It In, which requires students to submit their papers for a plagiarism check when they submit them. Plagiarism.org also provides webinars to help teachers teach students about plagiarism. Doc Cop is a fee-based service that checks large documents for copied material.
Teachers can also prepare themselves to recognize potentially plagiarized material by being familiar with websites that sell term papers to students. Some of these, as of 2014, are Essay World and Essay Boy.