ACT Science case studies
ACT Science · Put your knowledge to work in context.
The ACT Science Test is the science portion of the ACT, a college admissions exam used by U.S. colleges and universities. According to ACT, more than two million students take the ACT each year, and the test is offered in both digital and paper formats, with the science section available as an optional add-on. ACT lists the Science Add-On fee at $5.00. The ACT Science case studies are 5 cases and about 1,594 words.
1Interpreting a Fertilizer Runoff Experiment with a Confounded Control
A student studies algal growth in pond water. She fills four 500 mL beakers with pond water and adds fertilizer solution: 0 mL, 2 mL, 4 mL, and 8 mL.
360 words, about 2 min2Deciding What a Correlation Between Ice Cover and Fish Mass Means
A lake ecologist records the date of spring ice breakup and the average mass of adult perch caught each year for 15 years. Earlier breakup dates are associated with larger average perch mass (r = 0.68).
315 words, about 2 min3Reading a Graph of Enzyme Activity vs. Temperature with Missing Error Bars
A student measures the activity of an enzyme at 10, 20, 30, 40, and 50 °C. Activity rises from 5 to 30 units between 10 and 30 °C, peaks at 30 °C, then falls to 20 units at 40 °C and 4 units at 50 °C.
306 words, about 2 min4Choosing the Right Control When Testing a Cleaning Product
A company tests a new spray cleaner on kitchen counters contaminated with a known amount of bacteria. They spray the cleaner, wait 5 minutes, and swab the counter.
288 words, about 1 min5Reasoning About Sample Size and an Outlier in a Plant Growth Study
A student grows 30 bean plants: 15 in plain soil and 15 in soil with a worm castings amendment. After 4 weeks, mean height is 18.2 cm (plain) and 21.0 cm (amended).
325 words, about 2 min