CoStudy

HomeCertifications › 4th Grade Science

4th Grade Science practice questions and exam guide

25 multiple-choice questions and 75 flashcards, written to the Next Generation Science Standards blueprint. Every question carries a full rationale.

Written and maintained by Nick Burton · last updated 2026-08-22 · how we write and review questions

Study 4th Grade Science in CoStudy →

About the 4th Grade Science exam

Next Generation Science Standards (NGSS) — Grade 4: Energy (4-PS3), Waves (4-PS4), Molecules to Organisms (4-LS1), Earth's Place in the Universe (4-ESS1), Earth's Systems (4-ESS2), Earth & Human Activity (4-ESS3). Public standards from nextgenscience.org.

CoStudy's 4th Grade Science bank holds 100 items. Every multiple-choice question carries a written rationale explaining why the correct answer is correct and why each distractor is tempting but wrong.

Free 4th Grade Science practice questions

A sample of 12 multiple-choice questions from the bank, with the full rationale shown.

Energy is:

  1. Always lost
  2. Solid matter
  3. Only heat
  4. The ability to do work or cause change

Answer: D — The ability to do work or cause change

Energy = capacity to do work. (A) energy is conserved; (C),(B) too narrow.

A fossil of a sea creature found on a mountain suggests:

  1. Sea creatures lived on mountains
  2. Climate doesn't change
  3. The mountain was once under sea
  4. Fossils are fake

Answer: C — The mountain was once under sea

Mountain land was once seafloor — uplift over time. (A),(B),(D) wrong.

Leaves help a plant by:

  1. Absorbing water
  2. Storing seeds
  3. Anchoring the plant
  4. Photosynthesis (making food)

Answer: D — Photosynthesis (making food)

Leaves do photosynthesis. (A) is roots; (C) is roots; (B) is fruit.

To reduce flooding from storms, people might:

  1. Pave more roads
  2. Drain rivers
  3. Cut all forests
  4. Build storm barriers, plant trees

Answer: D — Build storm barriers, plant trees

Barriers and vegetation reduce flooding. (A),(C),(B) worsen it.

When light bounces off a mirror, that's:

  1. Reflection
  2. Refraction
  3. Absorption
  4. Diffusion

Answer: A — Reflection

Reflection = bouncing off. (B) is bending; (C),(D) different.

Animals get energy from:

  1. Sunlight directly
  2. Food they eat
  3. Soil
  4. Wind

Answer: B — Food they eat

Animals consume food for energy. (A) is plants; (C),(D) wrong.

A plant's flower's main job is to:

  1. Reproduce (make seeds)
  2. Absorb water
  3. Provide shade
  4. Capture sound

Answer: A — Reproduce (make seeds)

Flowers → reproduction. (B) is roots; (C),(D) wrong.

Waves can carry:

  1. Energy
  2. Matter only
  3. Nothing
  4. Heat only

Answer: A — Energy

Waves transfer energy. (B) waves transfer energy not matter (mostly); (C),(D) wrong.

When two cars collide, energy:

  1. Disappears
  2. Transfers to motion, sound, and heat
  3. Becomes mass
  4. Doubles

Answer: B — Transfers to motion, sound, and heat

Energy is conserved but transferred. (A),(C),(D) wrong.

Erosion is when:

  1. Rocks stay still
  2. Soil/rock pieces are moved away
  3. Trees grow
  4. The Sun rises

Answer: B — Soil/rock pieces are moved away

Erosion = transport of weathered material. (A),(C),(D) wrong.

A simple circuit needs:

  1. A power source, conductor, and path that loops
  2. Just wires
  3. A magnet only
  4. Just a switch

Answer: A — A power source, conductor, and path that loops

Circuit = closed loop with source + conductor. (B),(C),(D) incomplete.

A renewable energy source is:

  1. Coal
  2. Oil
  3. Solar (Sun)
  4. Natural gas

Answer: C — Solar (Sun)

Solar is renewable. (A),(B),(D) finite fossil fuels.

4th Grade Science flashcards

6 sample cards from the 75 in the bank.

How does ice cause weathering?

Water seeps into cracks, freezes, expands. Pushes rocks apart.

What are the main parts of a plant?

Roots, stem, leaves, flowers, fruit, seeds.

What is 'frequency' of a wave?

How many waves pass a point per second. High frequency = high pitch (sound) or color toward blue (light).

What is a 'non-renewable resource'?

Can't be replaced quickly — once used up, it's gone. Examples: oil, coal, natural gas, minerals.

Why is energy important to all living things?

Energy is needed for everything life does — moving, growing, breathing, thinking.

How does a fish's body help it survive?

Streamlined shape for swimming, gills for breathing in water, fins for steering, scales for protection.

Practise the full 4th Grade Science bank

These samples are a small slice. The full bank runs flashcards, multiple choice and timed mock exams with per-chapter progress tracking, on the web and in the iOS app.

Open 4th Grade Science →

4th Grade Science — frequently asked

How many 4th Grade Science practice questions does CoStudy have?

The 4th Grade Science bank holds 100 items: 25 multiple-choice questions, 75 flashcards. 18 of them are on this page to read free, with no signup.

Do the 4th Grade Science questions come with explanations?

Yes. Every multiple-choice item carries a written rationale that states the controlling principle behind the correct answer and then addresses each wrong option in turn — why it tempts and precisely where it fails. Knowing why the plausible answer was wrong is worth more than knowing which letter was right.

What is on the 4th Grade Science exam?

Next Generation Science Standards (NGSS) — Grade 4: Energy (4-PS3), Waves (4-PS4), Molecules to Organisms (4-LS1), Earth's Place in the Universe (4-ESS1), Earth's Systems (4-ESS2), Earth & Human Activity (4-ESS3). Public standards from nextgenscience.org.

Are the 4th Grade Science practice questions free?

The samples on this page are free to read in full, rationales included, with no account. The complete 100-item bank, the timed mock exams and per-chapter progress tracking are part of CoStudy on the web and in the iOS app.

How current is the 4th Grade Science content?

Last reviewed 2026-08-22. Banks are written against the certifying body's published exam outline and re-checked when that outline changes — exams get renumbered, retired and reweighted, and a bank written to a superseded outline teaches the wrong proportions. Figures that are re-indexed annually are deliberately not asserted as rules; the questions test the governing principle instead.

Related study guides

Related subjects

Browse all 222 study banks →