With the major stumbling block being on chemistry being difficult in high school, with the periodic table being the most difficult thing about high school, there is method to this madness. First, grade school kids should know that chemistry is all about mass - the more mass there is to equal size, the further down it goes, okay? With that, there is more protons, and, with more protons there are more electrons, okay? This is because the more and more, this is to say that it gets denser and denser, if you will, leads to heavier things, so, with there being more mass, there is also more weight per atom. This means that every step to the right or down leads to a heavier more dense element. Particles make up elements, and, that is physics, which we will cover briefly later, of course.
Now, with each element being unique in that it also has orbitals, where the electrons that are not paired with protons, as in a electron that makes up a electron, where the mass of the electron is split, due to the similar charges between the cloud, and, that leads to a field from each electron segment where they will split more and more due to the amount of protons, where they seek each proton. This is sort of like where a drop of blood in a pool of water will spread out, okay? The electrons merely splits, due to the wave function, where the waves, as they say they are waves, get between the crux of the electron itself!
Anyway,
The elements will be placed into groups where they subscribe to various states of being, where they are gas, semi metal and easily turned into gas with heating or metal with condensation, and, metals. I like to call the semi metals liquids, as, I believe in the four elements, of course, but that is just me, I suppose...