Use reusable, recyclable materials--along with a dose of imagination--to build a castle with first grade geometrical forms.

Your 1st grade scientist will improve her observation skills as she's encouraged to eat healthy by comparing the dry and fresh fruit in this experiment.

Put a twist on traditional oil painting with this fun science activity that you and your first grader can do together.

Teach your first grade scientist the difference between liquids and solids using maple syrup.

Water can go from solid to liquid to gas...but how does popcorn go from kernel to snack? Invite your first grade scientist to find out.

First grade science often covers solids, liquids, and gases. This silly science explores serious facts about the difference between all three.

Here's a fun activity to help build thinking skills in young first grade scientists, and to encourage them to have a blast exploring the mass and volume.

Chemistry is a blast with this backyard bomb made from a sandwich bag. All you need are ingredients from the pantry to create a satisfying, and safe, explosion.

Make meringues with your first grader and see how states of matter can transform before your very eyes. Here's how:

Help your first grader explore the world of scientific measurement by "weighing" fruit with a "water scale"!

Did you ever think you could make colors disappear right before your eyes? This science experiment is just like a magic trick: now you see it, now you don't!

In this science fair project, young children discover what happens when two fluids that have different densities get together.

This science exploration lets your first grader see how eggs can provide a perfect environment for a living, growing creature.

This project demonstrates the correspondence between the volume of water displaced by a submerged object and the volume of the object displacing it.

Do this experiment to help your first grader understand how salt can be removed from salt water. All it takes are a few household materials.

Here's a science activity that lets a first grader use an empty dish detergent bottle to create his own fountain as he explores air pressure.

This easy Halloween-themed science experiment for first-graders is perfect for chilly October afternoons or great as a Halloween party activity.

Explore solids and liquids with your young scientist by making gluep, a goopy substance that can behave like both a solid and a liquid!

In this sound experiment children listen for differences as they tap on a bag of air, a bag of water, and a wooden block held up to their ears.

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

Play this flashlight game with your child to teach him about objects that are transparent, translucent, and opaque.

Bring the magic and mystery of the night sky to the light of day with this fun constellation art project!

Explore the scientific concept of capacity by seeing how many pennies you boat can hold before it sinks!

How do we know that air exists when we can't see it, taste it, or touch it? Here's a classic experiment that will teach your kid some basics of aerodynamics!

Is it solid or liquid? Create oobleck and witness the amazingly weird oscillation between the two!

Teach your child about using pumps to move water in this simple and educational preschool science activity!

This classic children's game demonstrates how sound travels through air vs. through a solid.

What's cooler than an explosion? Not much! This simple science experiment lets kids build their own pop rocket. So put on your safety goggles and let her rip.

In this Halloween-themed activity, young learners will find out what happens when they mix two household items together to create a surprising chemical reaction.

Here's a classic celery science experiment that uses celery and food coloring to demonstrate how plants absorb water.