The most comprehensive site for this specific workbook is OnlineGDZ.3dn.ru , which provides a step-by-step breakdown by Einheit (Unit) and exercise number.
Онлайн ГДЗ. Ответы к "Горизонты" рабочая тетрадь 5 класс gdz po nemetskomu iazyku 5 klass averin tetrad
Most platforms organize the answers according to the textbook's structure: Units 1-7: Core vocabulary and grammar exercises. Fitnesscenter Deutsch: Review sections to prep for tests. Kleine Pause: Intermediate review and games. The most comprehensive site for this specific workbook