Science · Year 3 · Working Scientifically: The Young Researcher · Summer Term

Making Predictions and Hypotheses

Students will learn to make simple predictions and form hypotheses based on their scientific questions.

• National Curriculum Attainment Targets
• KS2: Science - Working Scientifically

About This Topic

Making predictions and hypotheses teaches students to think like scientists by anticipating experiment outcomes and proposing testable explanations. In Year 3, children construct simple predictions, such as 'The wooden block will sink in water,' and form hypotheses like 'Paper boats float because they trap air.' They learn predictions differ from guesses through justification using prior knowledge or observations, such as patterns from playground tests or class discussions on materials.

This skill anchors the Working Scientifically strand of the National Curriculum, linking to units on plants, rocks, and forces. Students practise fair testing by planning what to change, measure, and observe, building confidence in evidence-based reasoning. Teachers guide them to phrase predictions clearly and revise hypotheses after results, promoting resilience in scientific enquiry.

Active learning benefits this topic most because students engage directly with materials during prediction-testing cycles. Group experiments, like racing toy cars down ramps with varied surfaces, let children voice ideas, record results, and debate revisions collaboratively. This hands-on process makes abstract thinking concrete and memorable, deepening understanding of the scientific method.

Key Questions

1. Construct a clear prediction for a given experiment.
2. Explain the difference between a prediction and a guess.
3. Justify a hypothesis based on prior knowledge or observation.

Learning Objectives

• Formulate a clear prediction for a simple science experiment based on a given question.
• Differentiate between a scientific prediction and an uninformed guess by providing justification.
• Construct a hypothesis for an investigation, using prior knowledge or observations as evidence.
• Evaluate the outcome of an experiment against a stated prediction and hypothesis.

Before You Start

Making Observations

Why: Students need to be able to carefully observe phenomena to gather information that informs their predictions and hypotheses.

Asking Scientific Questions

Why: Formulating a clear question is the first step in the scientific process, leading directly to the need for predictions and hypotheses.

Key Vocabulary

Prediction	A statement about what you think will happen in an experiment. It is an educated guess based on what you already know or have observed.
Hypothesis	A proposed explanation for an observation or phenomenon, often stated as an 'if, then' statement. It is a testable idea that can be supported or refuted by evidence.
Justification	The reason or evidence given to support a prediction or hypothesis. This can come from prior knowledge, observations, or previous experiments.
Observation	The act of noticing and describing events or processes in a careful, orderly way. Observations help form predictions and hypotheses.

Watch Out for These Misconceptions

Common Misconception

A prediction is the same as a guess.

What to Teach Instead

Predictions rely on evidence like past observations, while guesses lack reasoning. Role-play activities where students justify predictions before testing help them articulate differences. Peer feedback during group trials reinforces evidence-based thinking over random ideas.

Common Misconception

Hypotheses cannot change after testing.

What to Teach Instead

Science involves revising ideas based on new evidence. Experiments with variable outcomes, like plant growth under lights, show students how to adapt hypotheses. Structured reflections after trials build flexibility through active discussion.

Common Misconception

No need to justify predictions.

What to Teach Instead

Justification links ideas to knowledge, strengthening scientific rigour. Prediction stations prompt students to note reasons before testing, with group shares highlighting weak justifications. This active process clarifies the value of evidence.

Active Learning Ideas

Pairs: Ramp Prediction Challenge

Pairs build ramps with books and test toy cars on different surfaces like carpet or foil. First, they predict which surface allows the fastest roll and justify with observations. Then, they time three trials per surface and compare results to predictions.

30 min·Pairs

Small Groups: Dissolving Hypotheses

Groups hypothesise which solids dissolve fastest in water, such as sugar versus sand, based on particle size observations. They add equal amounts to jars, stir for one minute intervals, and draw conclusions. Discuss revisions to initial ideas as a group.

45 min·Small Groups

Whole Class: Shadow Length Predictor

Display a lamp and objects; class predicts shadow changes with light distance. Measure and record in a shared chart, then test predictions by adjusting lamp positions. Vote on best hypothesis and explain why.

35 min·Whole Class

Individual: Plant Growth Guess or Predict

Students observe seeds in pots and individually predict sprouting time based on watering differences. Track daily in journals, then share if predictions held and why. Compare to mere guesses from peers.

25 min·Individual

Real-World Connections

• Meteorologists make predictions about the weather, like 'It will rain tomorrow,' based on scientific data and models. They form hypotheses about how atmospheric conditions will change to explain these forecasts.
• Engineers designing a new toy car might predict how changes to the wheels will affect its speed. They form a hypothesis that 'smoother wheels will make the car go faster' and then test it through experiments.

Assessment Ideas

Exit Ticket

Provide students with a scenario: 'You are testing if plants need sunlight to grow.' Ask them to write: 1. A prediction for the experiment. 2. One sentence explaining why they made that prediction. 3. A hypothesis for why plants need sunlight.

Quick Check

During a hands-on activity, ask students to hold up a card showing 'Prediction' or 'Guess' after you pose a question. Then, ask them to verbally justify their choice using information from the lesson or prior experience.

Discussion Prompt

Present two statements about an upcoming experiment: Statement A: 'I think this ball will bounce higher because it's bigger.' Statement B: 'I think this ball will bounce higher.' Ask students to identify which statement is a prediction with justification and which is a guess, and explain their reasoning.

Frequently Asked Questions

How do you teach the difference between predictions and guesses in Year 3?

Start with everyday examples, like predicting rain from dark clouds versus guessing a football score. Use anchor charts comparing 'evidence-based prediction' to 'random guess.' Follow with paired think-alouds on simple tests, such as floating objects, where students must cite observations. This builds clear distinctions through repetition and application, typically in 20-minute sessions.

What activities help Year 3 students form hypotheses?

Hands-on tests like mixing baking soda and vinegar for fizz predictions work well. Students observe first, form a 'because' hypothesis, then test and record. Rotate materials weekly to practise across topics, ensuring hypotheses stay simple and testable. Link to curriculum units for relevance.

How can active learning help students understand predictions and hypotheses?

Active learning engages students through prediction-testing-revision cycles in collaborative experiments, such as ramp races or dissolving challenges. They voice ideas, test immediately, and adjust based on data, making the process tangible. Group discussions after trials reveal misconceptions early, while individual journals track growth. This approach boosts retention by 30-50% over passive teaching, per curriculum research.

Common mistakes when teaching predictions in primary science?

Teachers often accept vague predictions without justification, blurring lines with guesses. Overloading with complex experiments confuses young learners. Address by scaffolding with sentence starters like 'I predict... because...' and starting with familiar contexts. Regular low-stakes practise across units embeds the skill effectively.