I know this question has been asked before but I have only found threads for it at an undergraduate's level of understanding and I am just finishing ninth grade. How does the double slit experiment prove superposition? What led me to ask this question, was that, since when you close one slit the pattern you would otherwise see if both slits were open disappears, it must mean that the electrons are going through both slits simultaneously(In a ted talk about Schrodinger's cat). But, the diagram showed that electrons were being sent individually through each slit. Couldn't this mean that the reason the pattern isn't being seen is because the electrons are only being sent through one slit instead of two? Maybe, now that there is only one slit, it is harder to identify the wave pattern. It just seems like a real jump to say that, pattern disappears, therefore superposition. I tried to read this paper on the double split experiment, but I can't comprehend the Math yet, so it's essentially useless. Can you please give me an explanation that a high schooler can understand? P.S I am not debating whether or not the double split experiment shows an example of superposition. Based on the number of times this test has been done with the same conclusions again and again I can guess it is almost definitely correct. But I just can't seem to understand it.