Most primary schools in Russia use standardized programs. You likely need GDZ for one of these major authors:
Using GDZ isn't just about "copying"; it can be a powerful educational tool if used correctly: 2-4 klass gdz po russkomu jazyku 2, 3, 4 klass
Primary school is the best time to automate skills in phonetics, lexis, and basic grammar to ensure success in later grades. Most primary schools in Russia use standardized programs