This paper describes the online dynamic examination application plugin named O.D.E.S., developed according to the open source software philosophy, where the CMS Wordpress is used as programmers/coders are given the potential to develop applications from scratch with safety and ease. In ODES application there exists two types of users: admin/teacher and student. The admin/teacher can create/edit/delete/view questions, categories of questions and examination papers. The questions are divided in two types, multiple choice questions (including true/false) and long answer questions (essays). The teacher can create exams choosing the number of questions and the types of questions that exist in the pool of questions that are previously created. The selection is done randomly by the application and the teacher just determines the total number of both multiple choice or long answer questions as well as the importance (weight) of each one of them (including negative grades also). The student takes the random generated exam and receives his/hers grades. The grades of the multiple choice questions are done automatically, whereas for the long answer questions the teacher is responsible to put grades on. After the completion of the exam the teacher can view the student's final score via the control panel or a report.