An effective early childhood curriculum can be learning how to read and write. Without learning how to read, we wouldn’t be able to communicate through this app, or through online school. We wouldn’t know directions, and we wouldn’t be able to enjoy stories. If we didn’t know how to write, I would not be able to help you figure out the answer to this problem, and your teacher wouldn’t be able to grade anything. Think about it, you ir entire education is based of being able to read and write.
Science is based on theories and tests, if someone has a theory they will test and if it is correct yippie! and if it isn't they will redo the test over until they get it correct or unless it is unsolvable.