If protons and electrons both have a charge, how come only electrons affect an atom's overall charge?
Each of the three subatomic particles play a role in the behavior of an atom. Neutrons, located with protons in the nucleus of an atom, change the mass of the atom, and have no affect on the atom's overall charge. Protons and electrons are both charged, positively and negatively respectively. The gain or loss of a proton to the nucleus of an atom changes the type of element that atom now is, such as oxygen losing a proton and becoming nitrogen. Electrons, however, can be gained and lost without affecting mass or element type, and create a positively or negatively charged atom. The gain and loss of electrons, creating what's called an ion, plays a big role in the way that atoms bond to another.
How are plants and photosynthesis important for animals?
Plants do all the photosynthesizing, so what application does that have for animals? In order to function properly, cells require glucose, and animals, as heterotrophs, have to consume their glucose from other sources (think the cheeseburger you had for lunch, or the fruit from breakfast). In order for these other sources to have glucose, it has to be created, which is where plants come in. Some of these sources supply animals glucose directly, such as plant products like fruits and veggies. Other sources have consumed the plant products, and have this glucose stored for animals to break down in their own digestive systems.
What is physical science and why should I care about it?
As an eighth grade teacher, I often see students struggle with an idea because, why should it matter to them? Sure, we get that apples fall because of gravity, and these little atoms make us up, but what does physical science really do for me beyond that? Physical science is the perfect blend of chemistry and physics, using the separate disciplines to build off one another, and understand, say, not just the parts of the atom, but why they behave the way that they do.