The aim of this research is to examine the extent to which certain sociodemographic characteristics of students and teachers, along with computer self-efficacy, attitudes towards the new media and the frequency of using the new media in instruction, can be regarded as predictors of constructivist teaching. The research was carried out on a sample of a group (N = 1528) of eighth-grade students (n = 1026) and class and subject teachers (n = 502) in primary and lower secondary school (ISCED level 1 and 2). Data was collected through survey questionnaires with relevant instruments. The results show that, in terms of students, their sociodemographic characteristics, a higher level of computer self-efficacy, more positive attitudes towards new media and more frequent use of new media, as separate factors, are significant predictors of constructivist learning. In terms of teachers, their attitudes and computer self-efficacy are significant, but their sociodemographic characteristics and the use of new media are not. The entire final series, both in terms of teachers and students, is a significant predictor of constructivist learning, where certain separate dimensions of predictor factors are more significant than others. The greatest variance of constructivist teaching, both in terms of students and teachers, can be explained by the attitude towards new media and computer self-efficacy rather than the use of new media in instruction, as confirmed by some previous theoretical assumptions. Although significant correlations were obtained, the results point to an occasional organisation of constructivist teaching. The possible reasons and implications of such results are explained in this paper.