I have been to three summer programs, two from the same organization and another one and I wanted to know if I can talk about my experiences and achievements on the Common Application? Also, would I mention how long I was at the programs? I wasn't sure since I would not consider them an extracurricular since they were one time experiences. I am a junior that's interested in studying medicine and or public health in some way and these medicine-related programs helped me learn and become curious about medicine and pursuing a future in those fields.
You definitely can (and should!) include those in applications. There's a part of the Common App called Activities that allows you to include these, even if they were one-time experiences. In addition, depending on the colleges that you apply to, some may have writing supplements that allow you to write about these summer programs, or you could maybe even work them into your Common App essay.
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