I always find the best way to handle such scenarios is to make a joke of it if you can. Most people wont sneer at you if you stutter, they end up feeling bad for you which is not what you should want and obviously not what they want. Diffuse the situation by making light of it. I dunno something like "Oh it's my turn to read? Ok but we may need a double lesson to get through it" or when you get stuck say "Oh you know what I mean and smile/laugh about it. It may not be how you feel deep down as it can be incredibly frustrating dealing with a stutter but it does make things easier when there is a bit of humour involved. People start to root for you and you will get through it and maybe even enjoy it eventually. Lets not forget as well there will be people who are not as good at reading as you are etc, people who are super shy etc. We all have our own battles we have to face. Don't let it bring you down.