Fourth Grade Earth Science

Getting Started

You are about to become a real geologist as you explore the world of rocks, crystals, gems, fossils, and minerals by moving beyond just looking at pretty stones and really being able to identify, test, and classify samples and specimens you come across using techniques that real field experts use.

While most people might think of a rock as being fun to climb or toss into a pond, you will now be able to see the special meaning behind the naturally occurring material that is made out of minerals by understanding how the minerals are joined together, what their crystalline structure is like, and much more.

Please login or register to read the rest of this content.

	Color Streak You will be able to identify minerals by their colors and streaks, and be able to tell a sample of real gold from the fake look-alike called pyrite.
	Mohs’ Hardness By the end of this lab, you will be able to line up rocks according to how hard they are by using a specific scale. The scale goes from 1 to 10, with 10 being the hardest minerals.
	Acid Test Your goal is to identify samples according to their reactivity with acid. Minerals that react are called chemical rocks, and minerals that don’t are called clastic rocks. Some chemical rocks contain carbonate minerals, like limestone, dolomite, and marble which react with the acid.
	Density Density can be found by weighing an object and dividing by the volume of the object, and for geologists, is the same thing as specific gravity. Water has a density of 1, which means that 1 gram of water takes up 1 cubic centimeter of space. Specific gravity is a number you get when you … Continue reading "Density"
	Magnetism A magnetic field is the area around a magnet or an electrical current that attracts or repels objects that are placed in the field. The closer the object is to the magnet, the more powerfully it’s going to experience the magnetic effect. Nearly all minerals that are magnetic have iron as a component.
	Rock Candy Crystals Crystals are formed when atoms line up in patterns and solidify. There are crystals everywhere — in the form of salt, sugar, sand, diamonds, quartz, and many more! To make crystals, you need to make a very special kind of solution called a supersaturated solid solution. Here’s what that means: if you add salt by … Continue reading "Rock Candy Crystals"
	Penny Crystal Structure The atoms in a solid, as we mentioned before, are usually held close to one another and tightly together. Imagine a bunch of folks all stuck to one another with glue. Each person can wiggle and jiggle but they can’t really move anywhere. Atoms in a solid are the same way. Each atom can wiggle … Continue reading "Penny Crystal Structure"
	Laundry Soap Crystals Can we really make crystals out of soap? You bet! These crystals grow really fast, provided your solution is properly saturated. In only 12 hours, you should have sizable crystals sprouting up. You can do this experiment with either skewers, string, or pipe cleaners. The advantage of using pipe cleaners is that you can twist … Continue reading "Laundry Soap Crystals"
	Salt & Vinegar Crystals We’re going to take two everyday materials, salt and vinegar, and use them to grow crystals by creating a solution and allowing the liquids to evaporate. These crystals can be dyed with food coloring, so you can grow yourself a rainbow of small crystals overnight. The first thing you need to do is gather your … Continue reading "Salt & Vinegar Crystals"
	Eggshell Crystals Geodes are formed from gas bubbles in flowing lava. Up close, a geode is a crystallized mineral deposit that is usually very dull and ordinary-looking on the outside. When you crack open a geode, however, it’s like being inside a crystal cave. We’ll use an eggshell to simulate a gas bubble in flowing lava. We’re … Continue reading "Eggshell Crystals"
	Salt Stalactites This is a continuation of the Laundry Soap and Rock Candy experiments, so make sure you’ve done those before trying this one.

Getting Started

Select a Lesson