The workbook "Математика. 6 класс. Тетрадь для контрольных работ" by I.I. Zubareva and A.G. Mordkovich is a common Russian educational resource used for assessing student performance in the 6th grade. Digital versions and control tests are available on educational platforms such as Lecta and Uchebnik.mos.ru, while solutions are typically found on sites like GDZ.ru.