tailieunhanh - Jossey-Bass Teacher - Math Wise Phần 9

Cho học sinh hoạt động này, họ sẽ cần phải ngăn xếp cam, như cửa hàng tạp hóa đôi khi. Yêu cầu họ làm thế nào họ nghĩ rằng ngăn xếp cam ở lại chất đống mà không rơi xuống. | How To Do It 1. Tell the students that for this activity they will need to stack oranges as grocery stores sometimes do. Ask them how they think orange stacks stay piled up without falling down. Discuss how the stacks are usually in the shape of either square- or triangular-based pyramids. Then allow the students to begin helping with the orange-stacking experiment. 2. The players might begin by analyzing patterns for square-based pyramids of stacked oranges because these are sometimes easier to conceptualize than pyramids with triangular bases. Have them predict and then build the succeeding levels. The top Level 1 will have only 1 orange. Challenge students to determine how many oranges will be required for the next level down Level 2 . After discussing the possibilities for Levels 3 and 4 build the structure as a class. Ask students how they might determine the number of oranges that would be needed to build an even larger base Level 5 given that there are not enough additional oranges to build one. 3. It may be sufficient for young students to predict and build the structures for Levels 1 through 4. As they build students in grades 2 through 5 will develop their logical-thinking skills. Older students grades 6 through 8 however will often logically analyze the orange-stacking progression and be able to discover a pattern and eventually a formula for determining the number of oranges at each level. Students will find that from the top down Level 1 1 orange Level 2 4 oranges Level 3 9 oranges Level 4 16 oranges and Level 5 will require 25 oranges. Have students determine how many oranges will be needed for Levels 6 8 10 or even 20 instructing them to write a statement or a formula that they can use to tell how many oranges will be needed at any designated level see Solutions . 4. When they are ready students can be challenged with stacking oranges as triangular-based pyramids. With 35 oranges participants will be able to predict build and analyze Levels 1 through