6th grade is the year of "н" and "нн" in adjectives. Knigina's tests are famous for tricky spelling tasks in this area.
This blog post provides an overview and study guide for the by M.P. Knigina . This workbook is a staple for Russian 6th graders looking to master grammar and prepare for future exams like the OGE and EGE. gdz testy po russkomu iazyku 6 klass 2 chast knigina
The second part of this workbook focuses on the heavy-hitting topics of the spring semester. Key sections typically include: 6th grade is the year of "н" and "нн" in adjectives