Wanting to do the speech will help, deading it will not help. I know this might not be possible with an English speech but if you are at least interested and engaged in your work then it will go better. I also find that for me, it is better to not look at specific people but just above or to the right of people and to slowly look around the room or to give the speech to inanimate objects in the room that are in the direction and at the height of the students. And finally: you have to remember that if they have any compassion or thought that they will not care if you stutter. I am in the workforce and while of course there's not really anyone who makes fun of stuttering. That is for elementary schoolers. So, give it your best shot and the mature people in your class will understand. Certainly your teacher will not care.