Fair Tests Today

Overview

This lesson (Lesson 2 of 4) focuses on designing and carrying out a simple fair test experiment using testable questions, variables, and data collection. Students build on Lesson 1 by turning ideas into a plan they can conduct and measure.

Learning intentions

Students will be able to:

• identify a testable question and choose an appropriate fair-test approach
• distinguish independent, dependent, and controlled variables in an experiment
• conduct an investigation with repeated trials and record organized observations
• use evidence from collected data to support early conclusions and next steps

Success criteria

Students can…

• write a testable question and predict an outcome based on evidence
• label independent, dependent, and controlled variables for their experiment
• collect data in a table or chart with consistent units and include multiple trials
• explain what their data shows and name one improvement for a future trial

Curriculum links

• SC.5.N.1.1 — The Practice of Science: define a problem, plan/carry out investigations, collect/organize data, interpret information in tables/graphics, analyze, and defend conclusions
• SC.5.N.1.4 — The Practice of Science: identify a control group and explain its importance in an experiment
• SC.5.N.1.3 — The Practice of Science: recognize and explain the need for repeated experimental trials
• SC.5.N.2.1 — The Characteristics of Scientific Knowledge: science is grounded in empirical, testable observations
• SC.5.N.1.5 — The Practice of Science: understand authentic investigations may not follow every step of a “scientific method” exactly

Lesson structure (45 minutes)

1. 0–5 min · Hook (Introduce fair tests). Teacher displays the introduction slides and prompts: “What makes an experiment a fair test?” Students turn-and-talk, then share one idea: variables, control, or repeated trials.

2. 5–12 min · Mini-lesson (Variables + control). Teacher uses the introduction slides to show a sample scenario and model labeling independent, dependent, and controlled variables, plus a clear control group; Students complete quick “check your thinking” prompts verbally with the class, then add the labels to their own experiment idea on the planning sheet.

3. 12–20 min · Planning station (Method + safety). Teacher introduces the required experiment structure using the introduction slides: steps, equipment, how data will be recorded, and what stays the same (controlled variables). Students finalize their plan in small groups and confirm:

• what they will change (independent variable)
• what they will measure/observe (dependent variable)
• what stays the same
• what their control group is (if applicable to their setup)

4. 20–28 min · Set up + run Trial 1. Teacher distributes and reviews the experiment data worksheet expectations: organized data table, units, and space for Trial 1 results; Students set up materials, run Trial 1, and record measurements immediately.

5. 28–36 min · Run repeated trials (Trial 2/3). Teacher uses the introduction slides to emphasize repeated experimental trials and asks, “Why might results change even if the same method is used?” Students complete Trial 2 and Trial 3 (or at least 2 trials if time is tight), record all results, and circle any outliers to discuss later.

6. 36–43 min · Analyze quickly (Evidence first). Teacher guides students to interpret their own data (mean/typical pattern, highest/lowest, or “same vs different”) using the introduction slides discussion prompts: “What does the data show? What evidence supports it?” Students write a short evidence statement on the experiment data worksheet (one sentence minimum).

7. 43–45 min · Plenary (Next steps + improvement). Teacher brings the class back with the introduction slides for a fast share-out: “Name one controlled change you kept constant and one improvement for next time.” Students exit by saying one improvement idea in groups (to prepare for Lesson 3).

Resources

• the introduction slides
• the experiment data worksheet
• Fair-test planning mat option for variable checks: the fair test planning mat (hand out to groups only if needed for structure)
• Lab materials based on experiment topic (pre-set at stations)
• Measuring tools (rulers, timers, balances, or thermometers depending on the chosen investigation)
• Data recording clipboards or deskside writing supplies (pencils, extra paper)
• Student safety expectations posted (eyes-on task, handle tools carefully)
• Timer for trial pacing

Assessment

• Teacher observation checklist during planning: variables labeled correctly and control group identified when applicable
• Formative data check: students’ tables show consistent units, clear measurements, and multiple trials recorded
• Formative explanation check: students’ “evidence statement” uses data language (numbers/patterns) rather than guesses
• Quick group talk at the end identifying one improvement for next time

Differentiation

• Support: Provide sentence starters on the experiment data worksheet (e.g., “Our independent variable was…”, “Our data shows…”) and model variable labeling before students start.
• Support: Offer the fair test planning mat to groups that need more structure for controlled variables, control group, and step-by-step method.
• Extension: Challenge advanced groups to calculate an average (if measurements support it) and propose a specific revision to improve reliability (tighten measurement technique, repeat more trials, refine the data table).
• EAL/SEN: Use visual cues from the introduction slides and allow students to record measurements with minimal text (numbers first, then one short evidence sentence).

Extension (optional)

None.