Use of tobacco, alcohol and cannabis among pupils in primary and secondary schools amount of pocket money per week / next to school having additional job like newspaperservice, working in supermarket / earnings / amount of money to spend per week / drinking alcohol, frequency of drinking alcohol / nr. of drinks at one time / last time drinking alcohol / what kind of alcohol been drinking last time / place where been drinking last time / amount of money spending on alcohol per week / attitude of parents to drinking of respondent / smoking cigarettes / nr. of cigarettes smoking per day / inhalating while smoking / attitude of parents to smoking of respondent / who is smoking in family - household / knowledge respondent of specific drugs / knowledge on how to use hasj, marihuana / ever used - using marihuana or hasj / frequency of use / last time used marihuana or hasj / attitude of parents to drug use of respondent / assessment of questionnaire by respondent. Background variables: basic characteristics/ place of birth/ residence/ characteristics of parental family/household/ education/ religion