Science Buddies: "Ask an Expert"

So I'm doing this superconductors project but I'm not sure if I understand the superconductors right but I was wondering how did they choose the substance to make an effective superconductors what is the reason behind it cause someone told me they are guessing but they can't guess all of it without any theory behind it at all right? So if you would kindly answer my questions that would mean a lot thank you and sorry for my bad english.

Hi Thanwarat,
I am afraid I am not familiar with the superconductor project. Can you post the link to it please?

In regards to the other part of your question, superconductor are usually grouped in a family based on their characteristics (similar to the arrangement of the periodic table.) Please take a look at the wikipedia page
https://en.wikipedia.org/wiki/Superconductivity

Good Luck!
Willey