Understand patterns, relations, and functions

• identify functions as linear or nonlinear and contrast their properties from tables, graphs, or equations.

• use symbolic algebra to represent situations and solve problems, especially those that involve linear relationships
• recognize and generate equivalent forms for simple algebraic expressions and solve linear equations

• model and solve contextualized problems using various representations, such as graphs, tables, and equations.

• use graphs to analyze the nature of changes in quantities in linear relationships.

• Understand such attributes as length, area, weight, volume, and size of angle, and how to select the appropriate type of unit for measuring each attribute
• Understand the need for measuring with standard units and become familiar with standard units in the customary and metric systems.

• Develop strategies for estimating the perimeters, areas, and volumes of irregular shapes.
• Select and apply appropriate standard units and tools to measure length, area, volume, weight, time, temperature, and angle size.

• Technological:
  Students must be able to:
  
  
  • perform basic mouse manipulations such as point, click and drag.
  • use a browser such as Netscape for experimenting with the activities.

• a jar containing a predetermined number of jelly beans in it.
• to have some pre-measured shapes drawn.

• Access to a browser
• Meter stick

1. Focus and Review
Hold up a jar of Jelly beans; explain to the class that whoever most accurately estimates the number of jelly beans contained in the jar will win the jelly beans.


2. Objectives
Students will use a variety of methods to estimate quantity, perimeter, and area.


3. Guided Practice
• Discuss the various different methods students used to estimate.
• Point out how some methods worked better than others.
• Open the Estimator applet and have students work through an example or two with you.

4. Teacher Input
• Instruct the students how to use the following applets:
  • More or Less Estimator
  • Comparison Estimator
  • Estimator
  • Estimator Four

5. Independent Practice
• Have the students get into pairs and work with the different estimation applets.
• Once all the students have had time to experiment with the estimation applets take them to the pre-drawn figures and have each group estimate and record the area and perimeter of each shape using inches, feet, centimeters, and meters.
• Have all the groups create a chart in Excel expressing each group's estimated areas for the different shapes along with the actual area of each shape.
• Have the students calculate the percent error.

6. Closure
• Investigate the variation in percent error.
• Discuss the different methods each group used for estimation.
• Discuss why some methods seemed to be more accurate than others.
• Discuss "real life" applications of estimation.