In October sky what three changes did homer and his friends do to improve their rocket designs?

In "October Sky," Homer and his friends made several key changes to improve their rocket designs. They experimented with different fuel types, switching to a more effective mixture to enhance thrust. Additionally, they refined their rocket's aerodynamics by streamlining the shape and adding fins for better stability during flight. Lastly, they incorporated better materials to withstand the heat and pressure during launches.