“…The frequencies of students' disruptive behaviours during classes of main subject were investigated in the researches of Alley et al (1990), Department of Education and Science and the Wales Office (1989), Jones et al (1995), Jones et al (1996), Lawrence and Steed (1986), Merret and Wheldall (1984), Wheldall and Merret (1988). The most frequently reported behaviours were "Speaking out of turn", "Avoiding work", "Idleness", "Disobedience", "Standing up".…”