Plan Fair Tests
Grade 4 - Science - Challenge Me
Fair-test plan: for the problem "a paper bridge must hold 20 washers," which test would compare solutions clearly?
- add washers one at a time until the bridge bends
- measure temperature in sun and under the cover at noon
- spray each package five times and check the seeds
- run a fan for one minute and measure sand moved
Which variable should stay the same while testing designs for "a shade cover must cool a playground thermometer"?
- the conclusion after testing
- tilt the fabric to block afternoon Sun too
- stretch light-colored fabric over the thermometer area
- uses one square meter of fabric
Evidence: close sticks lost less sand than wide gaps. Which improvement follows from the data?
- seal the envelope edges with tape
- keep the folded beams and strengthen the center span
- reduce gaps between the sticks
- tilt the fabric to block afternoon Sun too
Why should engineers repeat a test for "a model roof must drain rainwater away from a doorway"?
- repeating removes the need for measurements
- each trial should use a different criterion
- data should be ignored after one test
- repeated trials make the evidence more reliable
Which data table heading best fits a fair test for "a seed package must keep seeds dry"?
- title only
- weather, lunch choice, recess game
- solution tested, measurement, result
- favorite design, color, opinion
Fair-test plan: for the problem "a warning code must send three messages with light," which test would compare solutions clearly?
- run a fan for one minute and measure sand moved
- ask a partner to read the flash cards without hints
- measure temperature in sun and under the cover at noon
- pour the same amount of water on each roof model
Which variable should stay the same while testing designs for "a seed package must keep seeds dry"?
- the conclusion after testing
- uses one envelope and one coating material
- coat the envelope with wax paper
- seal the envelope edges with tape
Evidence: folded beams held 24 washers while flat paper held 9. Which improvement follows from the data?
- add longer pauses between messages
- keep the folded beams and strengthen the center span
- reduce gaps between the sticks
- make the side channel deeper
Why should engineers repeat a test for "a paper bridge must hold 20 washers"?
- each trial should use a different criterion
- repeated trials make the evidence more reliable
- repeating proves the first idea was perfect
- repeating removes the need for measurements
Which data table heading best fits a fair test for "a warning code must send three messages with light"?
- weather, lunch choice, recess game
- title only
- solution tested, measurement, result
- favorite design, color, opinion