Those things in the sixth grade of primary school (Author: Zi)
Primary School Mathematics Special Student Reader (Grade 6) (Author: Primary School Mathematics Special Student Reader (Grade 6))
Ingeniously calculating the sixth grade volume of interesting questions in primary school mathematics (Author: Li Shude, Zhang Yushan and other editors)
Interesting Mathematics Blog: Sixth Grade General Mobilization (Author: Rouxuan)
Primary school mathematics knowledge tree: Grade 5 and 6 (Author: Liu Kaiyun)
Skillful Calculation of Interesting Math Questions in Primary School —— Grade Six Volume (Author: Skillful Calculation of Interesting Math Questions in Primary School)
Little Black Horse Series Super Teachers Teach Writing (Grade 6) (Author: Xie Xie)
Math Puzzle Reader (Volume II) (Author: Mathematics Interesting Stories (I))
Chemistry (Grade 9) (Author: Chemistry (Grade 9))
You can download these under I love reading e-books.