This quote should hit every Christian like a ton of bricks. If you call yourself a Christian, you WILL be watched by others to see if you live out what you claim. The question is, when they look at you, what will they see? Will they see the fruit of the Spirit? They should.
Ephesians 1:13 tells us that when we believed in Christ for our salvation, we were sealed with the Holy Spirit. In other words, the Holy Spirit made a home inside our hearts when we gave our lives to Christ. Since the Holy Spirit dwells inside of us, we should be controlled by the Spirit in everything we do. When controlled by the Spirit, our lives will show it by producing: Love, Joy, Peace, Patience, Kindness, Goodness, Faithfulness, Gentleness and Self-Control.
Check out this verse from Ephesians 5:15-16: "Look carefully then how you walk, not as unwise but as wise, making the best use of the time, because the days are evil."
Where should you walk carefully? At home, at school, at parties, on sports teams, at lunch, at church, at the movies, when a friend spends the night, at school clubs, and every other place you go. Wherever you go, you represent Christ... make sure you represent Him accurately!
Gandhi also said, "If it weren't for Christians, I'd be a Christian." I hope no one at your school feels the same way based on how you live...