The goal of the present research was to assess the environmental worldviews and concerns of students from the fourth to the seventh grade in Slovenia. The New Ecological Paradigm Scale for Children was translated and validated for use with Slovenian primary school students (N = 310). The students were also asked about their environmental concerns (using statements from the Environmental Motives Scale) and demographic questions. A confirmatory factor analysis was conducted for the New Ecological Paradigm scale using AMOS software, confirming a three-dimensional model with ten items. The students showed the highest agreement with the items in the factor Rights of Nature, and the lowest agreement with Human Exemptionalism. The environmental attitudes of the students decreased from the fourth to the seventh grade, while altruistic environmental concerns significantly increased with higher grades. Gender differences were not statistically significant for environmental worldviews and concerns. The reported results show that biospheric environmental concern positively correlates with the factors Rights of Nature and belief in Eco-Crisis, and negatively correlates with Human Exemptionalism. The New Ecological Paradigm tool will enable the evaluation of education programmes for children in Slovenia.