Lesson 1 of 10

🔬 What Do Scientists Do?

🎯 Grades 3–5⏱ ~25 min💚 Beginner

What You'll Learn

  • Understand the scientific method — the steps scientists follow
  • Know the difference between an observation and a hypothesis
  • Practice asking good scientific questions

Scientists Are Question-Askers

A scientist is anyone who looks closely at the world and asks why. You do this every day! Why does ice melt? Why do plants grow toward sunlight? Why does a ball fall down instead of up?

Scientists answer questions by following a process called the scientific method:

  1. 👀 Observe — notice something interesting in the world
  2. Question — ask a testable question about it
  3. 💡 Hypothesis — make an educated guess at the answer
  4. Experiment — test your hypothesis carefully
  5. 📊 Data — record what actually happened
  6. 🥊 Conclusion — decide if your hypothesis was right or wrong
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Important!

It is perfectly fine if your hypothesis is wrong. Scientists learn just as much from experiments that don't go as expected. A "failed" experiment is never wasted!

Observation vs. Inference

An observation is something you directly see, hear, smell, touch, or taste. An inference is a guess based on what you observe.

  • Observation: "The plant's leaves are yellow."
  • Inference: "The plant might not be getting enough sunlight."

Good scientists always separate observations from inferences. They test their inferences before claiming they are true.

🔬 Virtual Lab: Build Your Experiment

Practice the scientific method! Fill in each step below to plan a real experiment.

Quick Check

What is a hypothesis?

AA proven scientific fact
BAn educated guess that can be tested
CA lab tool used to measure things

Which statement is an observation (not an inference)?

AThe puddle outside is smaller than it was this morning
BThe sun must have evaporated the puddle
CIt probably didn't rain last night

What should a scientist do if their experiment proves their hypothesis wrong?

AIgnore the result and try again until it works
BNever share the results
CRecord the result honestly — a wrong hypothesis is still valuable data