A concept rater module is utilized to automatically grade or score constructed responses based on a model answer. The concept rater module may be configured to accept a model answer as input. The model answer may be used as a grading key by the concept rater module. The concept rater module may be further configured to accept student responses in a file format. The file format may be ASCII text, a formatted word processing (e.g., WORDPERFECT, MICROSOFT WORD, etc.) and the like. The concept rater module may be further configured to process a student response into a canonical representation of the student response. The canonical representation of the student response is compared against the model answer by the concept rater module. From the comparison, a score is generated which represents that student's ability to cover all the key concepts.