1. The cover area of a math book is about 40 square centimeters, which is consistent with the actual situation. 4 square decimeters =400 square centimeters, and 400 square centimeters is 15 centimeters long times about 26.6 centimeters wide, which is the size of a book.
2, 4 square centimeters, this area is too small, a book can not be as big as 4 square centimeters, 4 square centimeters is 2 centimeters long and 2 centimeters wide. The length and width of this book are all over 2 cm.
3,400 square centimeters, which is too big.
Children's skills in learning primary school mathematics well;
1, learn to preview actively
Before explaining new knowledge, it is an important means to read the teaching materials carefully and develop the habit of previewing actively.
Therefore, cultivate self-study ability, learn to read books under the guidance of teachers, and preview with teachers' carefully designed thinking problems.
For example, if you teach yourself an example, you should find out what the example is about, what the conditions are, what you want, how to answer it in the book, why you answer it like this, whether there is a new solution and what the steps are.
Grasp these important problems, think with your head, go deep step by step, and learn to use existing knowledge to explore new knowledge independently.
2. Summarize the law of solving problems in time.
Generally speaking, there are rules to follow in solving mathematical problems. Gradually improve and persevere, children's psychological stability and adaptability to solve problems can be continuously improved, and their thinking ability will be exercised and developed.
3. About homework
In the process of doing homework, there is a psychological state of being quick and careless when examining questions. For wrong questions, guide students to form a wrong question analysis method. The purpose of the analysis is to make students fully realize the problem-solving errors caused by incorrect reading, thus forming the intrinsic motivation of "I want to read correctly" and guiding students to carefully examine the questions and truly understand the meaning of the questions.