How to make my friend say yes to the talent show?

Well this year, I really want to partake in the talent show. I really feel like singing a duet with my guy friend, since he is a bit of a singer. But, he really doesn't want to. He has been thinking about it, and I give him space so I don't seem too pressuring. He keeps giving me excuses like he has stage fright or is a very poor singer. I haven't heard him sing, sorry, but I really don't care. I want to make this school year really memorable and worth everything that I've gone through. What else can I do to make him feel confident enough about himself to know he is worth singing in the talent show? I don't know what else to do. The try outs are near the end of April '11, so I have about 4 months for him to let me know. Actually a little less, since we would need practice and rehearsal. Thanks again! :)