unfortunatly, we are not able to answer our on-line questions daily, so I hope you were able to find some support through this. Remember you can always speak to a teacher or your principle about fears you may be having.
one way to deal with standing in front of a crowd is to remember that nervous energy is still energy, and can be used to support your presentation. find your grounding. take a few deep breaths, and look above the crowd (not directly at them). take a few seconds to calm your heart down and control your breathing, then put your nervous energy into your presentation. let it support a strong, loud voice. It is benificial to practice this before you stand in front of a crowd. Go someplace where you can be nice and loud and vision yourself giving a great performance despite your nervous energy.