1. Observation method: For a square or rectangular figure, the number of squares can be judged by observing its side length and the number of grids. Assuming that the side length is n and the number of cells is m, then the number of cells is n× m, for example, a square is divided into 9 squares equally, and each side has 3 squares (because 3×3=9), so there are 9 squares in total.

2. Calculation method: For a complex figure, it can be divided into several squares or rectangles, and then the number of squares in each part is calculated separately, and finally the sum is made. For example, a field-shaped pattern can be divided into four rectangles, and each rectangle is divided into 3×3=9 squares on average, so there are 4×9=36 squares in total.

3. Multiplication: We can use the symmetry of the grid to simplify the calculation. If the side length of the grid is a power of 2 (for example, 2x2, 4x4, 8x8, etc. ), we can get the result quickly through recursive calculation. For a 2×2 grid, the number of squares is 4.

In the process of doing math problems, we can take better methods to master the problems.

1, summary questions: summarize each question type, understand its problem-solving ideas and methods, and form your own problem-solving system. It is necessary to clarify the topic type to which the topic belongs. For example, algebra problems, geometry problems, probability problems and so on. Collect questions, do problems or record new problems when you are studying.

2. Take notes: analyze and record the key points, difficulties and mistakes in the topic, which will help deepen memory and understanding. Before taking notes, make clear the purpose of recording. Is it to record the problem-solving methods and important steps, or to record your own mistakes and reflections? A clear purpose helps to record more pertinently.

3. Multi-angle thinking: Try to think about problems from different angles and find different ways to solve problems, which is helpful to cultivate flexibility and creativity in thinking. For every mathematical concept or theorem, we can start from its original definition, think about the essence and characteristics of this concept or theorem, and find a solution.

4. Draw inferences from one example: train the topic with variants and try to change the conditions and conclusions, so as to gain a deeper understanding and mastery. Try to change the conditions of the topic and let students think about how to solve the problem in this case. For example, when solving an equation, we can try to change the number of coefficients or unknowns in the equation, so that students can think about how to re-apply the solution of the equation.