Uncovering inexpensive, simple techniques to encourage students to act in a pro-environmental manner is of critical importance. Through a four-week field study at a large, environmentally focused elementary school, it was found that placing negatively valenced emoticons (i.e., red frowny faces) on trash cans increased the proportion of recycled material from 22% to 44%. Subsequently, through a controlled laboratory study at a recognized "green" university, it was found that the negatively valenced emoticon increased the percentage of students who recycled their provided paper from 46% to 62%. Therefore, using emoticons as a complement to existing environmental education may be an easily implementable technique to positively change the recycling behavior of both older and younger students.