Kónya, György2018-01-282018-01-282016-072064-2199http://hdl.handle.net/2437/247563environmental educationproject based learningself-assessmenteducation for sustainable developmentChanges in the Environmental Attitudes of Secondary School Studentsfolyóiratcikkopen access journalDebreceni Egyetemi KiadóDOI:10.14413/HERJ.2016.02.08Hungarian Educational Research Journal22016Kónya, György2018-01-30Research Papers