Grade: Grade 6 Subject: Science Unit: Experimental Design Lesson: 6 of 6 SAT: ProblemSolving+DataAnalysis ACT: Science

Unit Checkpoint

Unit Assessment

A student wants to test if fertilizer affects plant growth. She sets up 20 identical plants: 10 get fertilizer, 10 get plain water.

What is the independent variable?

What is the dependent variable?

Which group is the control group?

Name three variables that should be kept constant.

Write a hypothesis for this experiment.

Why does she use 10 plants in each group instead of 1?

Is "the plants look healthier" qualitative or quantitative data?

What would be a quantitative measurement she could take?

If results don't support her hypothesis, what should she do?

How could she improve the experiment's reliability?

Click to reveal answers

1. Fertilizer (presence or absence)

2. Plant growth/height

3. The 10 plants receiving plain water

4. Amount of water, sunlight, soil type, temperature, plant species, pot size

5. Example: "If plants receive fertilizer, then they will grow taller than plants without fertilizer."

6. Larger sample size provides more reliable results; reduces effect of individual variation

7. Qualitative (descriptive observation)

8. Plant height in cm, number of leaves, leaf size, stem diameter

9. Report actual results, revise hypothesis, design new experiment

10. Repeat the experiment, increase sample size, have others replicate it

Score	Mastery Level	Next Steps
9-10	Advanced	Move on to the next unit!
7-8	Proficient	Review missed concepts, then proceed.
5-6	Developing	Review lessons 3-5 before moving on.
0-4	Beginning	Restart the unit from Lesson 1.