1. Concession
Concession statements are necessary, especially if in your thesis you take a strong stand.
Concession statements acknowledge (NOT DEFEND!) a contrary thesis or contrary theses that might be argued by someone else.

2. Certainly, grades do serve as a powerful motivational tool for students. The fear of failure gets otherwise disengaged students to complete their work, and the desire to receive excellent marks (A's) motivates good students to push themselves to do their very best work. It is also true that grades contribute to a productive classroom environment that benefits the entire group; students will do their homework if they know they receive a grade, thus improving the quality of class discussions. On the other hand, the positive motivational effects are overpowered by the negative impact of competition between students. Students who don't earn those A's often feel like failures, even though they have learned a great deal. Students often are disappointed with a B because its not an A. Often students compare their grades with others in an effort to see how they rank. This relative status has little to do with how much an individual is actually learning. In short, we must find another way to motivate students that puts the emphasis on learning rather than on the delineation of winners and losers.

3. Key Words to Use
I. Phrases to introduce the concession It is true that... Admittedly,... Granted,... Certainly,... Of course,... II. Phrases to introduce the counter argument However,... Nevertheless,... On the other hand,... But... III. Phrases to introduce the conclusion Thus,... Therefore,...