This practical activity is to let students solve practical problems by comparing their existing knowledge, experience and relevant knowledge. Further understand the application value of comparison and enhance the interest and challenge of mathematics learning. This textbook is divided into two parts. The first part is to guide students to explore and discover the law that the ratio of height to shadow length is equal when measuring bamboo poles with different lengths at the same time and place. The second part is "discussion and doing", which inspires students to solve the practical problem of "how high is the tree" by discovering the law.
Analysis of learning situation
Students have learned comparative knowledge and some measurement knowledge, and have already got a preliminary perceptual knowledge. It shouldn't be difficult to learn this content. As long as students are clear about the content, purpose and some details that should be paid attention to when operating. Students have mastered the basic learning methods of cooperation, discussion, communication and induction, and have given full play to them in learning activities.
Teaching objectives
1. Through the process of experiment, comparison and exploration, it is found that the ratio of height to shadow length of bamboo poles with different lengths measured at the same place is equal.
2. Through group cooperation, cultivate students' ability to solve practical problems and the spirit of unity and cooperation.
3. Through activities, students can feel the close connection between mathematics and real life, further stimulate their interest in learning mathematics, and cultivate innovative spirit in activities.
Teaching emphases and difficulties
Focus: Use the knowledge of ratio to solve practical problems.
Difficulty: guide students to find the law through experimental comparison.
teaching process