Periodic Table Lesson Plans for the 8th Grade
The History of the Atom: A Detective Story
- Middle school students will know what an atom is, but introducing the scientific discoveries that correctly describes an item too small for its discoverers to even see makes a fascinating detective story. Greek philosophers active centuries before the birth of Christ posited the existence of atoms as the smallest building block of matter. Capture students' imaginations by having them prepare reports about the key scientists in the development of atomic theory, including Democritus, John Dalton, J.J. Thomson, Ernest Rutherford and James Chadwick. Have others report on what would be different in the world without the knowledge of atoms and their components. This is an opportunity to engage students with chemistry by showing them how scientists, even in primitive circumstances, can use the scientific method to arrive at amazing insights. At the end, students should understand the roles of electrons, neutrons and protons.
Electronegativity: The Role of Electrons
- The basis of each element is its atomic structure and to help students understand the Periodic Table, the makeup of elements in general is a good starting place. The elements of atoms are the building blocks of the Periodic Table, and it's important that students understand that each atom in elements is unique. If you continue to cut a piece of iron in half, for instance, you will end up with one atom of iron. Develop projects that illustrate the atomic bond that makes a combination of electrons, protons and neutrons one element and not another. Ask why gold is so valuable and iron isn't. Why does one rust and the other doesn't? Understanding the volatile nature of electrons in some elements is a key to understanding how chemical reactions are born.
The Periodic Table: Issues
- By now, students understand the makeup of elements. It's time to teach the entire table and explain why some elements are grouped together by various attributes. This is a good time to explain groups and have the students research a group of elements in groups. What identifies these groups? Why do some disappear as soon as they form? This might be a good time to run a "Jeopardy" game, giving the answer and asking what the question is. Let teams use their notes to identify elements. Kids like things that explode; use elements to show explosions when introduced to water or other substances.
- No one expected atomic theory to result in a horrific bomb. Many scientists, including Einstein, were angry that their research was used for killing. However, nuclear energy has been used to explore our galaxy. What uses in the future will benefit mankind? This is a major issue, as we have seen in the meltdown of plants in Japan, Russia and at Three Mile Island in the United States. How can plants be made safer? Why are underlying geographic structures important? Allow students to contribute their ideas;