27 Science Riddles with Answers for Kids (FREE PDF)

Are you ready for a little science fun? Here are science riddles with answers that will get your students thinking (and smiling).

These clever science riddles are perfect for Chemistry and Biology classes. A few in this riddle collection will also work for younger kids.

Once you print out the free pdf of Science Riddles, head over to school riddles, math riddles, science jokes, and science puns.

Science Riddles with Answers for Kids

Have some science fun with these science riddles.

• You will find me in Mercury, Earth, Mars, and Jupiter, but not in Venus or Neptune. What am I? – The letter R.
• What is the moon’s worth? – $1, because it has 4 quarters.
• What can be measured, but has no length, width, or height? – The temperature.
• You can’t see me, but I can see you. To be more specific, I see through. What am I? – An X-ray.
• At night they come without being fetched. By day they are lost without being stolen. What are they? – The stars.
• What has a mouth but can’t chew? – A river.
• Lots of people have heard it, but no one has seen it. It will not speak back unless spoken to. What is it? – An echo.
• It is very hard to create me, but I can’t be destroyed, I can only change form. What am I? – Energy.
• I am the child of the water, yet when I return to the water, I die. What am I? – Ice.
• I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I? – Subconscious Mind.

Chemistry Riddles

These science riddles are specifically for chemistry lovers.

• I’m in your kitchen pantry, waiting for you to wrap me over something. What am I? – Aluminium.
• What is black when you purchase it, red while you are using it, and gray when you discard it? – Charcoal.
• What four periodic elements, when combined, make up something that terrifies criminals? – Carbon, Oxygen, Phosphorous, and Sulfur (C + O + P + S).

• If bananas were to have a chemical formula, what would it be? – BaNa2.
• I am a gas that is essential for plants, but I can’t be bought at the gas station. What am I? – Carbon dioxide.
• I am a god, I am a planet, and I can measure the temperature. What am I? – Mercury.
• I can be sparkling, I can be still, I am a liquid and something you can spill. What am I? – Water.
• If you get me as a medal it means that you have done your best. I am what you find in abundance in a hidden treasure chest. What am I? – Gold.
• Occasionally associated with smelly things, what state of matter am I? – Gas.
• I am a unit of chemical elements, but I can never be trusted. What am I? – An atom, they make up everything.

Biology Riddles

• Anyone can hold me, even without their hands, yet no one can do it for long. What am I? – Breath.
• I am under your face and outside your mind. What am I? – Skull.
• I am a ball that can be rolled, but never bounced or thrown. What am I? – The eyeball.
• I am hard as a stone but you can find me on your body. What am I? – Teeth.
• Without me as a part of your brain, you would lose your posture and balance, and be unable to coordinate muscle movements. I always hang out near my good friend the brainstem. What am I? – Cerebellum.
• I am three-quarters of the universe and almost nothing is known about me. What am I? – Dark matter.
• I can be good for you, I can be bad. You can find me all over your body. What am I? – Bacteria.

Add your favorite science riddle to the comments.