Mentors for Elementary
Type of Activity:
- Group/cooperative learning
- Elementary outreach
- Integrated science class benefits by helping elementary students
Mentor day occurs one or two times each year. A group of upper level science students develops and practices demonstrations and hands-on activities that they present to a sixth grade elementary class. There are several goals. First, the high school students acquire knowledge and confidence as they help younger students succeed in science activities. Second, the elementary students benefit from seeing cheerleaders, football, track and basketball team members as successful students. Third, the number of students electing to take more science classes will increase.
This project helps high school students academically by requiring them to learn the material and activities that they present to an elementary group. (As all teachers know, you learn more as the teacher than as the student.) This activity is a winning situation for all involved - high school students, elementary students, elementary teachers and the coordinating high school teacher. The high school students participate in a learning project in which they apply their knowledge to help younger students; the elementary students learn new science concepts as they develop a love for science and a desire to learn more; the elementary and high school teachers benefit from the collaboration and exchange of ideas.
This project dispels the fear of science and creates a desire to learn science in the elementary students. An upper level science class develops and practices demonstrations and activities that they do with a sixth grade class. The subject of the demonstrations and activities is decided by the elementary teacher since she knows the needs of her students. The day and time for the activity are decided upon by the elementary and high school teachers. If the high school students have another class during that time the principal must agree to their absences.
The high school students must have class time to develop and practice the demonstrations and hands-on activities. The amount of time is determined by the difficulty of activites and the capability of the students. If they feel sure of themselves, they will be able to walk into the elementary classroom and take over. They will be amazingly confident in their presentations if they have had ample time to practice.
Suggested Lesson ActivitesThat Relate Physical and Biological Sciences:
- Center of Gravity
- Nail acrobatics - Instruct students to balance 12 nails on one nail hammered into a two inch square block of wood.
(Note: Lay down one nail. Put one nail ACROSS that nail, lay the next nail in the opposite direction until all 10 nails are lying on the one nail. Now put the 12th nail PARALLEL to the first nail and put the head at the opposite end. Now gently put your fingers to the ends of the first and last nail you put in place. Pick up all the nails and balance on top of the nail in the block of wood. That is the center of gravity of all 12 nails.)
- Instruct students to stand about two feet from a wall. Put their heads against the wall so that there is a 90-degree angle between their head and wall, hips and thighs, feet and floor. Lean over to pick up a chair that is between them and the wall and then strand up while holding the chair and without moving their feet. They cannot bend their knees.
(Note: The person's center of gravity will not allow the person to stand up. Usually all the girls can do this and the boys cannot. This shows that the center of gravity is different in boys and girls - usually)
- Coin in a Cup - Place a penny on an index card that is placed on top of a plastic cup. Instruct the student to thump the card. What happens and why?
(Note:The card will move forward and the coin will drop into the cup. Why? The coin has inertia so it remains at rest and gravity pulls it down into the cup.)
- Hard boiled or raw egg? Instruct the student to spin the eggs and hypothesize which egg is the raw egg.
(Note:The raw egg will continue to spin even after it is touched slightly. The boiled egg will stop immediately after it is touched slightly. Why? The liquid inside the raw egg has inertia and will continue to move even after the shell stops. There is no liquid inside the boiled so it does not continue to spin.)
Extension - try to stand the raw egg on its end. It is next to impossible. After shaking the raw egg for one minute, try again to stand the raw egg on its end.
(Note: Shaking changes the center of gravity so it should now be possible to stand the raw egg on its end.)
- Instruct the student to spin in a circle and stop. Why does he feel dizzy?
(Note: The fluid in the middle ear continues to spin even after the student has stopped spinning. His eyes send his brain a message that he is standing still but his ears send a message that he is still spinning. Confusion makes the student feel dizzy.)
- Raisin float - Put raisins into a cup of water with one alka-seltzer tablet. What happens and why?
(Note: Carbon dioxide produced from the alka-seltzer collects on the raisin. This gives the appearance of altering the density of the raisin so that it floats. Does the density of the raisin really change? When the carbon dioxide escapes into the air, the density of the raisin is increased and it sinks until more carbon dioxide collects on the raisin again.)
- What is the density of a human body? Devise an experiment to determine the density of humans.
(Note: If a person relaxes in a horizontal position in water, let's assume that one-tenth of their body will stay above the top of the water - their density is nine-tenths that of water which is 1 g /1 cm3)
Extension - How would the above experiment change if the person were in salt water, rather that fresh water? Let the student experiment with a boiled egg, a cup of fresh water and a cup of salt water.
(Note: The egg in salt water will float, the egg in fresh water will sink. If the student now applies the results of the activity with the egg and salt water to a human body they should conclude that more than one-tenth of the body will stay above the top of the salt water. The saltier the water, the higher the body will float.)
- Sound waves
- Do sound waves travel faster through solid or gas? Instruct students to tie two strings to the opposite ends of a coat hanger. Hit the coat hanger against the edge of a table. Listen to how the sound travels through air. Now with the strings wrapped around the student's fingers, stick the fingers in the ears, hit the coat hanger against the edge of the table and note how the sound travels through the solid string.
(Note: Sound travels faster through a solid than through a gas.)
- The coat hanger made in the above activity can be used to listen to the student's own heart. This is the principle behind the production of stethoscopes. Now would be an appropriate time to teach students how to take their own blood pressure by using a sphygmomanometer, cuff and stethoscope.