Substance abuse, or drug abuse is excessively and repeatedly using chemicals to change perception or achieve a different state of mind. Substance abuse has many causes, the most common ones include, peer pressure, academic stress, teenage depression or other untreated emotional or physical causes. Being a teacher, it is important to understand and help your students, even the ones abusing substances, and noticing the signs of drug abuse is the first step toward a positive change.Teachers and students interact on a daily basis, this makes it easy for a teacher to notice subtle behavioral changes and signs of drug abuse in a student. With close observation one can easily spot the signs of substance abuse among your students and help them take appropriate action for finding help. Importantly, remember that many signs of drug abuse exist, and its a cardinal sin to presume without being sure.All students are at a risk of coming under the kind of influence that encourages drug use. Pretty much any student might abuse drugs, no matter what the student’s background is. There are some symptoms though, that make it more likely for a student to try drugs. These include a family history of drug abuse, depression and other mental illnesses, a low self esteem and antisocial behavior.A student who is abusing drugs, is likely express disinterest in any extracurricular activities that might happen in the school. Such students will lack the enthusiasm to partake in school work, hobbies, sports or even making new friends or maintaining old ones. Its quite likely for them to develop a rebellious and unfriendly attitude, be unhygienic, display improper grooming and isolate themselves from everyone else.The physical signs of drug abuse are also quite noticeable. Some of the physical symptoms of drug abuse include, bloodshot red eyes, dark circles, coughing, wheezing, runny nose, sore throat and pale skin. While any unwell student can display these symptoms, a drug user will always have, all or some of these symptoms.The most obvious of all signs of drug abuse among students is the change in academic performance. Here are some generally accepted indicators of a student abusing drugs.1) Quality of homework and other schoolwork decreases significantly.2) Daydreaming or sleeping during lessons and displaying an intense lack of interest.3) Almost always late, takes long breaks and leaves for home early.4) Is often absent from classes.5) Appears confused and cannot concentrate.6) Doesn’t care for anyone’s, including their own, safety.7) Makes basic errors in judgement and has trouble performing easy tasks.8) Avoids all other students.9) Makes excuses and blames other for own mistakes.10) Claims that things are perfect and nothing has changed.11) Is suddenly losing or gaining weight.When looking for the above signs do keep in mind that the above symptoms can be caused by issues that are not drug induced. Sometimes a depressed child, or one with a mental illness or problems at home can behave quite similarly to a child abusing drugs. It is important to do your research and not accuse a student blindly.