一篇高中数学教案范例

Mathematics: Calculating the Area of a Circle

Sunshine State Standard Benchmark MA.B.1.4.1: The student will use concrete and graphic models to derive formulas for finding perimeter, area, surface area, circumference, and volume of two- and three-dimensional shapes, including rectangular solids, cylinders, cones, and pyramids.

Write the objective

Given six diagrams of circles in which either the diameter or radius is specified, students will determine the area of the circles using the formula Area=πR2. Students must show their work and solve at least five of the problems correctly.

Introduce the lesson

• Gain student attention– Show two Fri*****ees™ of different sizes. Ask students if they have ever played Fri*****ee™ and thought about how the size of the Fri*****ee™ might affect how far it will go when thrown? Tell them that a Fri*****ee™ or disk is really a circle, and the surface is called the area. In this lesson, they will learn how to determine the area of a circle.

• Explain the objective– Today they are going to learn how to determine the area of a circle. They will learn how to find the area when they know the radius of the circle and when they know the diameter. Use the Fri*****ee™ to point out the area, radius, and diameter.

• Relate to prior knowledge– Use prompting questions and statements to remind students of the following:

- vocabulary for the parts of a circle: circumference, diameter, radius (Draw and label the parts on the board.)

- the definition and value of π (π = 3.14 or 22/7)

- the formula for the circumference of a circle (Circumference=πD)
Present the content

• Knowledge and skills in lesson– Students already know vocabulary for the parts of a circle and the formula for the circumference of a circle. The lesson content will focus on calculating the area of a circle.

• Teacher and student learning activities – Write the formula for the area of a circle on the board and explain it (Area=πR2). Model and describe several examples, step by step, using the formula when the radius is known. Use the Fri*****ee™ as the first circle.

• Draw circle diagrams and write the problem-solving steps on a transparency as you explain the examples. Then, have the students work two problems with you. Ask prompting questions to guide learning at each step in the process.

• Repeat the process described above to teach how to determine the area of a circle when the diameter is known, adding in the extra step required (dividing the diameter by 2 to find the radius).

• Activity organization and support –
Media selection: Gather two different-sized Fri*****ees™. Secure an overhead projector and transparencies. Prepare two different worksheets with four circles printed on them for guided and independent practice. Prepare an assessment including six diagrams of circles, three with the diameter specified and three with the radius specified.
Student grouping: The introduction and the content are presented to the whole class. Guided practice is a small group activity.

Provide practice and feedback

• Guided practice– Have students work in groups of four to determine the area of four circles printed on paper, where either the radius or the diameter is given. Ask students to follow the problem-solving steps demonstrated in the lesson, showing their work on the back of the sheet of paper. After the first problem is solved, have one person in each group present the steps to the solution to the other group members and discuss it with them. After the second problem is solved, have a different group member present the solution. Continue until all four problems are solved and each group member has had a turn presenting the solution. Rotate among groups to coach students where needed and provide feedback on their performance. Next, go over all of the problems together with the class, showing each step in the problem solving process on overhead transparencies. Provide feedback on why responses are right or wrong. If needed, provide additional examples and additional opportunities for practice and feedback.

• Independent practice– Assign a homework exercise for independent practice. Give each student four circles printed on paper with different areas than those used in the guided practice activity. Have students determine the area of the four circles, where either the radius or the diameter is given. Ask students to show the steps in their work on the back of the page. Check the homework with the class the next day in the same manner described for guided practice.

• Judicious review – Preview the remaining lessons in the unit and determine appropriate places to include a short review of calculating the area of a circle.

Summarize the lesson

Remind students they have learned how to find the area of a circle.
Ask them to state the formula used and tell the extra step that must be taken first if only the diameter is known. Point out that this skill could be applied to finding the area of any circle, for example, the area of the top of a round table, etc. Write an additional circle problem on the board, have students solve it, and discuss responses.

Assess student learning

Give students a worksheet including six diagrams of circles, three with the diameter specified and three with the radius specified. The directions tell students to determine the area of each circle using the formula Area=πR2 and show the steps in their work. Students must solve five out of six problems correctly to demonstrate mastery. The solutions must include the steps and the correct answer.

Accommodations

For a student who has difficulty maintaining attention and working with other students in small groups:

• Provide practice and feedback
Within the small group, pair the student with a trained peer who can help keep his work on track.

• Monitor the group’s interactions and provide positive reinforcement to the student for appropriate behaviors.
For a student with poor visual acuity

• Introduce the lesson and Present the content
Make sure the student can see the visual aids for the lesson by making markings on the worksheets dark and legible. If needed, provide a large print handout with formulas and other key points for the student to read at his or her desk.

For a student who has poor fine motor control and writes very large:

• Assess student learning
Provide extra sheets of paper for the student to show the steps in the problem solutions so the solution does not have to fit into small spaces. Let the student use a word processor to complete the assessment.

所有跟帖： 

• Thanks~~~ (Is there any for mom/dad? :p) -huangme- ♀ (0 bytes) () 03/29/2006 postreply 08:09:17

• I'm not sure what you're looking for? :) -西西妈- ♀ (0 bytes) () 03/29/2006 postreply 08:24:33

• 十年前没有"组织指导"，荒废了偶儿的大好时光 Sigh... -huangme- ♀ (0 bytes) () 03/29/2006 postreply 09:08:40

• Very detailed, and emphasize good understanding -冰豆沙- ♀ (38 bytes) () 03/29/2006 postreply 08:38:09

• http://www.cpt.fsu.edu/ESE/in/desin/hsplan.html -请注明(ZT)- ♀ (0 bytes) () 03/29/2006 postreply 09:16:07

• 这就不对了，人家明明已经说了是范例。 -松子儿- ♀ (26 bytes) () 03/29/2006 postreply 09:28:47

• 文章都是有人辛苦劳作的. 范例也不例外. -请注明(ZT)- ♀ (48 bytes) () 03/29/2006 postreply 10:01:57

• 你还真好玩啊，范例不就是sample吗？ -松子儿- ♀ (68 bytes) () 03/29/2006 postreply 10:07:26

• 谁的范例? -请注明(ZT)- ♀ (0 bytes) () 03/29/2006 postreply 10:11:56

• Who is 傻子? you ? -working_Mom- ♀ (0 bytes) () 03/29/2006 postreply 10:06:12

• 阿毛教导我们说：请不要人身攻击！引用别人文章要注明是对作者的尊重 -十话- ♂ (0 bytes) () 03/29/2006 postreply 10:42:49

• Very goos! 引用别人文章要注明是对作者的尊重 -jj_2006- ♀ (0 bytes) () 03/29/2006 postreply 14:16:28

• 多谢西西妈，帮助我们了解美国中小学是如何教孩子的。 -NDMom- ♀ (10 bytes) () 03/29/2006 postreply 09:59:21