Bones Movie Background Information for Teachers and Parents
This page contains information to support educators and families in teaching K-3 students about bones and the skeletal system. The information is designed to complement the BrainPOP Jr. movie Bones. It explains the type of content covered in the movie, provides ideas for how teachers and parents can develop related understandings, and suggests how other BrainPOP Jr. resources can be used to scaffold and extend student learning.
Bones are a kind of hard endoskeletal connective tissue that is found in all vertebrates. Bones give bodies their structure and protect internal organs. Muscles are attached to bone and they contract and relax to allow movement. The adult human body has 206 bones; the smallest is the stirrup, which is inside the ear. It is less than an inch long. Children are born with 300 bones–some consist of hard connective tissue and others are made of cartilage. Over time, the cartilage hardens and turns to bone and some bones fuse together. This accounts for the larger number of bones in children than in adults. This is also why younger children tend to fracture more bones than adults—young bones are more flexible. Furthermore, children are more inclined than adults to take risks with their bodies and break bones.
Bones are made up of three layers. The outermost layer is called the periosteum. It is a thin membrane that covers the bone and contains nerves and blood vessels to nourish the bone. Bones can grow and change and need oxygen and nutrients just like the rest of the body. The next layer is called compact bone. This is smooth and very hard. Under the compact bone are many layers of cancellous bone. Cancellous bone is spongy and not quite as hard as compact bone. These layers make bones light but strong. In the middle of the bone is marrow, which produces two kinds of stem cells. Hematopoietic stem cells produce blood cells (white blood cells, red blood cells, and platelets) and stromal stem cells produce fat, cartilage, and bone.
There are many bones in the human body, and your children should be able to identify the major bones. The skull is a set of 29 bones in the head that protects the brain. The ribcage includes the ribs and sternum and together they protect the heart and lungs. We recommend watching the Lungs movie together as a review. The spine is a set of vertebrae and cartilage along the back that hold the body up. It goes from the pelvis all the way up to the neck and the base of the head. Joints are places where bones meet. Some joints allow for a wide range of movement, such as the joints in elbow and knees, and other joints are rigid. Though some joints contain cartilage and are not technically considered bones, other joints begin as cartilage and grow into bone, such as the rigid joints in the cranium.
Bones can break, but they can also heal. As soon as a bone breaks, the body begins developing tissue to heal the bone. At first the tissue is soft, but over time it turns into hard bone. Doctors will apply a cast to some broken bones in order to stabilize the body and allow for proper healing. For serious fractures, in which bones are broken into a few or many pieces, doctors can insert steel rods to support the broken bones to help them heal.
Discuss bone health with your children. How can they care for their bones? They can use helmets, knee pads, elbow pads, and wrist guards when riding bikes, skating, or skateboarding. Following rules is also an important part of staying safe and making sure they don’t harm others. Calcium helps build bones, maintain them, and make them strong. Encourage your children to eat calcium-rich food, especially now as they grow and change, such as milk, cheese, yogurt, and dark leafy greens. Vitamin D helps the body absorb calcium, which is usually found in dairy products and children’s vitamins. The body also converts sunshine into vitamin D. Regular exercise is vital to keep bones healthy. Strong bones as a child will help prevent osteoporosis and other bone diseases later in life.
