As one of the people who actually did well in high school science classes, I can safely say that nearly everyone in your class likely feels similarly. Just keep pluggin' along. You're likely almost halfway through the class.
Science is one of those subject areas that has a lot of information crammed into a single class. They're all general classes, typically, meaning literally every few weeks, you look at a different field under an umbrella of study. Physics gets broken down into motion, wave physics, particle physics, electricity, etc, Chem gets broken down into organic chemistry, ionic chemistry, etc, and Bio gets broken down into genetics, ecology, cellular biology, etc.
Your teachers are an invaluable resource. Science teachers typically *LOVE* talking about their subject matters. They went through years of learning to teach and to master their subject matter. There's a good chance they'll provide you with extra info and help you understand things if you're struggling.
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