In this video, students learn about another example of plants seeds. Gymnosperms are the oldest seed-baring plant. Students learn about their distinct appearance and life cycle.

In this video, students learn that plants create food through photosynthesis. For photosynthesis to take place plants have some basic needs. Different parts of the plant are used in photosynthesis.

In this video, students learn how some plants live and grow in certain environments. These plants must adapt to their surroundings to get their basic needs met and to ward off predators.

In this video, students learn that plants produce seeds in order to reproduce. When a seed is fertilized, with the right conditions, it will germinate, starting the life of a new plant. Students will see different seeds in the video.

In this slideshow, students learn the primary functions of roots and stems. They learn that roots do more than draw water and nutrients into the plant. Roots also help support the plant. Stems help distribute water and nutrients all over the plant and also support the plant's leaves and flowers.

In this slide show, students learn that sedimentary rock is naturally formed in the Earth's crust. It is formed when sediment deposits form layers, compact, and then cement together, creating a new rock. Sedimentary rocks are used for building materials, and sometimes they even contain fossils.

In this slide show, students learn that simple machines decrease the force, or effort, needed to lift and move heavy objects. There are several different types of simple machines, including levers, wheels and axels, pulleys, inclined planes,wedges and screws.

In this video, students learn about the causes of day and night. The resource illustrates the idea that as the Earth rotates, light from the sun hits different parts, giving us day and night. During its orbit, the Earth’s tilt on its axis also causes the two hemispheres to be different distances from the sun, and that gives us seasons.

In this slide show, students see an overview of the complex human body system. They learn that the human body is built with different cells. Similar cells get together to form tissues, like muscle tissue. All of these tissues form the organs that keep everything in the body running smoothly like the digestive and circulatory systems.

In this slideshow, students learn about the digestive system and how it helps turn food into fuel the body can use. It is made up of the mouth, salivary glands, throat, stomach, intestines, and bowels. The resource illustrates that food is necessary to fuel the body.

In this video, students learn that heredity is the passing of traits, or features, from parents to offspring through genes. Genes, which are found inside cells, are shared from one generation to the next, passing on all kinds of characteristics like eye color, dimples, freckles, and height.

In this slideshow students learn that the skeleton gives the human body a supporting frame and protects the internal organs. The resource illustrates that the skeletal system is attached to the muscular system, and they work together, allowing the body to move.

In this slideshow students will learn about the circulatory system. The resource illustrates that the circulatory system is a huge and complex system within our bodies that transports materials, blood and waste and is made up of the heart and blood vessels.

In this slideshow students will learn about the muscular system. This resource illustrates how the muscular system helps vital organs function, and it also performs another very important job. The muscular system is attached to the skeletal system, and that is what allows a person to move!

In this slideshow students learn about the respiratory system. The resource illustrates ideas that the lungs pull in oxygen through your nose, mouth, and throat. Then, in the lungs, the oxygen is transferred to the blood vessels and the lungs draw waste, carbon dioxide, out of the veins. Then a person can exhale all the waste!

In this slideshow, students learn that nerve cells throughout your body respond to exteranl stimuli by sending impulses to your brain. This allows your skin to respond to things it touches and provide protection.

In this slide show, students learn that Earth's moon reflects the sun, and so it is visible at night. It also rotates at the same rate that it orbits, 29.5 days, which means that we only see one side of it. The moon has one-sixth of the gravity of Earth and no atmosphere at all. Phases of the moon are also illustrated.

In this video, students learn that rock is a hard, solid material, consisting of one or more minerals, that makes up the Earth. Rocks continuously change from one type to another through the rock cycle process. There are three types of rocks: igneous, sedimentary and metamorphic.

In this video, students learn that volcanoes produce some of the Earth's most violent geologic changes, but they are not always violent. Different kinds of volcanoes produce different kinds of eruptions.

In this video, students learn that weather is a condition of the outside area at any time or place, and it is constantly changing. The climate, on the other hand, gives the big picture, or what the weather is like over a long period of time.