Start at home with the amount of water you use such as take shorter showers, lasting no more than 7-12 minutes or take only 2 minutes to brush your teeth (no leaving the water running). Then at school, when using paper of some sort, be sure to use the entire sheet especially if it's for notes or an assignment. Finally, try saving recyclable things such as paper and plastic until you reach the nearest recycling bin. Don't clutter of course but if you see some recyclable trash lying around, pick it up and try location the nearest bin