With several educational tests on different fields of the Dutch language, the level of education of pupils in the highest groups of primary schools is measured. Administrative items of the school: denomination, number of pupils, doubling rules, number of permanent functions in diverse fields, division of tasks, degree of urbanization of residence, consultative structures / administration of test and task participation of each school / tasks and tests concerning writing and speaking: technique, style, formulating, interaction, contents, communicative effectiveness, punctuation/ also speech act: passing information, description, summarizing, evaluation, giving instructions, obtaining information, argumentation / pupils: language used at home/ attitudes towards using language and situations in which the pupil is confronted with usage of language ( reading books e.g., writing, visits to the library, spending leisure time ). Background variables: basic characteristics/ place of birth