Topic
Similar Solids
Subject
Pre-Algebra I Prep
Objectives
- Learn the meaning of similar when applied to solids.
- Learn the effect of scaling a solid on volume and surface area of the solid.
Key Questions
- When are two solids similar?
- What is a scale factor?
- How does scaling a solid effect surface area and volume?
California Standards
Grade 7 Measurement and Geometry:
- 2.3 Compute the length of the perimeter, the surface area
of the faces, and the volume of a three-dimensional object built from
rectangular solids. Understand that when the lengths of all dimensions
are multiplied by a scale factor, the surface area is multiplied by the
square of the scale factor and the volume is multiplied by the cube of
the scale factor.
Procedures
The lesson plan will be divided
into the following activities:
- Warm-up by reviewing and correcting selected problems from
previous class worksheet (10
minutes)
- Hand back graded worksheets from the previous day.
- Students will be encouraged to help each other do the
selected problems since
"class
cash" for warm-up problem may depend on performance of randomly
selected group of students.
- At end of warm-up, teacher will do problems on overhead
projector.
- Introduce topic by drawing and/or showing solid examples of scaled solids. (10 minutes)
- 2 cycles of lecture and student attempts at
worksheet
(25 minutes). Cycle 1 will focus on effect of scale with relation to linear measures.
Cycle 2 will focus on effect of scale on volume and surface area.
- Teacher goes over how to do one category of problem.
- Students attempt several examples of this type of problem.
- Teacher goes over one additional example of problem after
they have attempted it on their own.
- Students are responsible for doing at least one
additional
problem of this type on their own (or with help from fellow students
and/or hints from teacher).
- Repeat cycle with more complex category of problem as
time permits.
- Class closure (5 minutes)
- Total up class money to reinforce classroom management.
- Dismiss class only after it comes to order.
Class worksheets will be graded and handed back the next day.
Due
to time constraints, worksheets are primarily graded on effort, not
correctness.
Assessment
- Student understanding of the
lesson will
be assessed real time by asking questions during lecture and by
observing/helping students when they do their worksheets.
- Student understanding will
be assessed by reviewing the worksheets after they turn them in.
- All material learned in this
lesson will be assessed in the companion pre-algebra class.
Student grades in the companion class will be reviewed on a
regular basis by the prep class teacher.
Resources
- Worksheets and notes generated by Mr. Brandon Matsumoto
with modifications as time permits.
- McDougal Littell California Middle School Mathematics
Concepts and Skills, section 10.8.
Reflection
Material
To be completed at end of lesson.
Classroom Management
To be completed at end of lesson.