Children -- especially young children -- often form their ideas about themselves based upon what other people say about them and how they behave toward them, according to therapist Brenna Hicks on her website The Kid Counselor. As a teacher, you assume the role of an influential figure in your students' lives, so by placing labels on students, you run the risk of shaping their self-images in negative ways. For example, if you label a student who misbehaves as someone who makes poor choices, that student might begin to think that she is a person incapable of making good choices, resulting in self-doubt.
Because students can internalize labels placed upon them, they are prone to allowing those labels to become self-fulfilling prophesies, according to Leah Gray in an article for Digital Journal. For example, if we label a child as a troublemaker, he might assume that the label is correct and that being a troublemaker is one of his innate qualities and roles in the world; therefore, he continues fulfilling that role. Additionally, even positive labels can stifle students' desires to branch out with their interests. For example, if a student exhibits athletic talent and is labeled an athlete, she might refrain from pursuing an interest in drama, feeling that arena must to be out of character for her.
Aside from how labels can affect the emotions and psyches of students, assigning labels also sends an inappropriate message to the surrounding student body: that it's okay to label people. What's so dangerous about this is the implicit condoning of labels taking place. Because labels aren't actively challenged and discussed, they are accepted as normal, harmless occurrences, which leads to their perpetuation by students, teachers and members of the surrounding community.
A final reason to practice caution when labeling a student is that labels often last a long time and affect how other people will treat the labeled student. For example, if you make it known that you feel a certain student is lazy, that student's other teachers might treat him according to that label. Because of your branding, teachers might be less patient or more demanding of the student's effort as a way to counter his perceived laziness.