GED Science case studies
GED Science · Put your knowledge to work in context.
This independent study page provides practice for GED Science. Its editorial learning areas include Scientific reasoning across life, physical and Earth science. The questions develop subject knowledge and application through worked reasoning, distinctions between competing answers, and practical scenarios. Study the relevant guide before attempting a mixed set, then explain the evidence or calculation that supports each answer. Topics on this exam: Scientific reasoning across life, physical and Earth science. The GED Science case studies are 4 cases and about 2,324 words.
1The Three-Plot Mulch Trial
A community garden volunteer wants to know whether shredded paper mulch keeps soil moister than straw mulch or bare soil. She marks three 2 m by 3 m plots along a fence. Plot 1, near a maple tree, gets shredded paper; Plot 2, in full sun, gets straw; Plot 3, partly shaded by a shed, is left bare. Each plot receives 4 L of water every Monday for four weeks.
621 words, about 3 min2Duckweed, Fertilizer, and a Shady Corner
Priya wants to know whether fertilizer runoff changes how quickly duckweed, a tiny floating plant, grows. She fills six identical 500 mL jars with 200 mL of pond water and adds 20 duckweed fronds to each. Three jars receive 5 drops of liquid fertilizer; three receive none. All six jars sit in a row on the same windowsill for 10 days.
554 words, about 3 min3A Sealed Plant Chamber
A class team seals a leafy potted plant inside a clear 2 L chamber fitted with a carbon dioxide sensor and a lamp. In bright light, CO₂ falls from 800 ppm to about 420 ppm over 20 minutes, then holds steady near 420 ppm even though the lamp stays on. The team then wraps the chamber in foil; over the next 20 minutes CO₂ climbs from 420 ppm to 610 ppm. When they uncover the chamber with the lamp on, CO₂ falls again.
561 words, about 3 min4The Falling Water Table
A farming town draws irrigation water from wells drilled into a sandstone aquifer. A nearby creek is fed partly by groundwater. Records from the town's monitoring well show the depth from land surface to the water table was 12 m in 2015, 15 m in 2018, 18 m in 2021, and 19 m in 2023. The creek's late-summer flow has shrunk each year and now stops entirely in dry Augusts.
588 words, about 3 min