🔬 ScienceGrade 2Lesson 38
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Simple Experiment Fair

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Learning Objectives

  • 1Design a simple science experiment with question, prediction, method, result, and conclusion
  • 2Change only one variable in an experiment to make results reliable
  • 3Present experiment findings clearly using evidence
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Mini Lesson

Real scientists share their discoveries with other scientists. In this project, you will choose a question from anything you learned this year, design a simple experiment to test it, carry it out, and present your results — just like a real science fair!

The five parts of an experiment

  1. Question: A clear scientific question you can test — for example, "Does a plant grow taller in sunlight or shade?"
  2. Prediction (hypothesis): What you think will happen — "I think ___ because ___."
  3. Method: The materials and steps to test your prediction. Change only ONE variable.
  4. Result: What you observed — numbers, sketches, and notes.
  5. Conclusion: Was your prediction correct? What does the evidence show?

Keeping your experiment fair

  • Change only one variable at a time — if you change two things, you cannot tell which one caused the result.
  • Keep everything else the same: same pot, same soil, same water, same time of day.
  • Record observations carefully with numbers, measurements, and drawings.
  • Repeat the experiment if you can — more trials make the result more reliable.

Sharing your work

  • Make a poster or folded display board with all five parts clearly labeled.
  • Practice presenting aloud: state your question, prediction, result, and conclusion.
  • Answer questions from your audience honestly — even "I don’t know yet" is a good answer.
The five parts of a science experimentA downward flow chart showing the five stages of an experiment: Question, Prediction, Method, Result, Conclusion — each in a labeled box connected by arrows.5 Parts of an Experiment1. Question2. Prediction3. Method4. Result5. Conclusion
A scientific experiment flows from question to conclusion in five ordered steps.
A fair test: one variable changedTwo plant pots side by side — one in sunlight, one in shade — labeled to show that only the light variable is changed while soil, water, and pot are kept the same.Change ONE VariableSunlightsame pot, soil, waterShadesame pot, soil, water
Only the light is different — everything else stays the same to keep the test fair.
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Write your five parts like a recipe: each step clear enough that a friend could repeat your experiment exactly the same way.

Vocabulary
Hypothesis
A testable prediction about what will happen in an experimente.g. "I think the plant in sunlight will grow taller."
Variable
The one thing you change in an experiment to test your questione.g. the amount of sunlight a plant receives
Observation
Information gathered by watching, measuring, or sensing during an experimente.g. "The shaded plant is 3 cm shorter after one week."
Evidence
Accurate, checkable data that supports or contradicts a hypothesise.g. a table of plant heights measured each day
Conclusion
A summary of what the evidence shows and whether the hypothesis was supportede.g. "Sunlight helped my plant grow taller — my prediction was correct."
Experiment
A careful test that follows a method to answer a scientific questione.g. growing two plants under different conditions to compare them
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