What is a “Performance Task?”An assessment exercise that is goal directed. The exercise is developed to elicit students' application of a wide range of skills and knowledge to solve a complex problem.

Why are we doing this?1) The core goals of the new PISD curriculum program

mandate it! (Specifically the science “transfer goals” which reflect the graduate profile.

2) Because it will stretch you beyond a paper and pencil test.

Is this something new?Not really. Every lab exercise in this class that hasn’t been a discovery activity has been a performance assessment of some kind. Your catapult project was a performance assessment, but more provided more structure and direction than this activity.

What is the task?Design a quantitative experiment to test the effectiveness of different insulation materials against radiant and/or conductive heat transfer.

•You may consider not only “household insulators” like fiberglass, cellulose, different kinds of foam, bubble wrap, reflective film, drywall, housewrap, etc., but also different materials and varieties of clothing.

•You should not compare household insulation to clothing as that would not be a valid, useful comparison in this context.

•More details in written handout.

This task will:

• Count as your major, summative assessment for this unit of study.

• Require that you think like a scientist.• Force you to think creatively on your own and

communicate with your peers.• Apply good scientific methodology.• Communicate your ideas and results in a formal way.• Connect your scientific conclusions to the real world

through a cost-benefit analysis.

Structure of the project

• Must work in groups (2-3) from the same class– Siblings exempted from same class requirement

• Proper lab reporting format at all stages• Realistically testable• Probably needs a “control” variable, possibly several• Must provide quantitative data• Must compare at least 4 different materials• Must have at least 10 different data sets• Your experiment cannot be the same as another group’s.

Keep your ideas private or both groups will be asked to re-write.

What you will turn in and when

• Complete experimental outline draft– (Purpose, Theory, Procedure)– 1/28, instructor review, student revise as needed

• Final experimental draft– (Purpose, Theory, Procedure)– 1/30, instructor check for completion/revisions

• Final complete lab report w/ cost analysis– 2/6 by the end of class– Time in class to work/write 2/4 & 2/5, bring

experimental elements to perform trials if desired

Project Rubric:First draft of purpose/theory/procedure: Content (5 pts) _____

Quality and Technique (5 pts) _____

Final draft of purpose/theory/procedure: Content (5 pts) _____

Quality and Technique (5 pts) _____

Lab report: (60 pts—see below) _____

Cost-Benefit analysis: (20 pts) _____

Final Score (100 pts total) _____

Lab Report (60%):(Each point below is equal to 4% of project grade)

Purpose and Theory: ____ / 4

Procedure: ____ / 1-2 (see next item)

Schematic w/ dimensions: ____ / 1 (if needed) (only needed if custom materials are used)

Data collected: ____ / 3

Analysis/Calculations: ____ / 3 (includes any charts, tables, graphs created AND a sample of every type of calculation performed)

Conclusions w/ error discussion: ____ / 3(a good conclusion might also include a discussion of extension to your experiment, how it could be improved upon or elaborated to work with additional variables, including future work suggested by your results)

YOU MUST KEEP YOUR RUBRIC TO TURN IN WITH YOUR LAB REPORT. IF YOU LOSE THE

GRADED COPY FROM THE SCORING OF YOUR FIRST DRAFT YOU WILL LOSE THOSE

POINTS!

Cost-Benefit Analysis

• To provide a basis for comparing projects. It involves comparing the total expected cost of each option against the total expected benefits, to see whether the benefits outweigh the costs, and by how much.

• You must determine how to logically normalize costs in your experiment so that you are comparing apples to apples.

• You must determine, on the basis of your data which material, in which arrangement provides the best insulation at the lowest cost.

CBA (cont’d)

• Attached to your final lab report, but as a separate document, basically a new page(s)

• This analysis will include both math and verbal explanations of your findings, and may include graphics that may help explain the comparisons made.

• No specific format is mandated, but it is encouraged that the paper product that you turn in be appropriate for a professional report.

• Be creative, but be mathematically appropriate.

CBA Example

• If you compared foam board to fiberglass to cellulose your cost-benefit analysis might look at the effectiveness of the product per inch of thickness per square foot of product, and then compared that result to the cost of the material in that arrangement.

• Similarly, for clothing you might compare the effectiveness of X number of layers/thickness of fabric to the cost per square foot of the garment or fabric.

Costs to you• Consider pooling resources with several groups so

that no student spends more than a few dollars on materials.

• Consider using materials that you may already own– Insulation could be removed from attic spaces, tested

and replaced (unless you cut it up)– Clothing you already own might be used (unless you

cut it up)• Students experiencing financial hardship should

speak to me in confidence. Discrete arrangements can be easily made.

SAFETY!• Please review the paper handout for specific

safety tips and experimental ideas.• Many insulating materials burn or melt under

the right conditions. Open flames are discouraged and radiant heat sources should be used with the utmost care and caution.

• Clear any procedures performed at home with your parents or a supervising adult.

• Unsafe experimental designs will lose points!

More safety issues

• Many home insulation products are skin irritants and can be an inhalation hazard.

• Wear appropriate clothing, hand and eye protection when using these materials.

• Read all labels carefully and MSDS sheets if available.

• Research safe handling procedures online from reputable sources prior to use.

Take care with water

• Wet materials often have different thermal properties than the same product when dry.

• Be sure any experiment using hot/cold water and/or ice protects the insulating material from dampness and that this control is incorporated into your procedure for all substances tests, or any deviations acknowledged in your report.