Does this work?
local Time = 0 Time.Changed:connect(function() Print("Time Changed") end
No, you can not use a Changed listening event on variables inside your script, unlike userdata. The reason for this is because roblox figures if you ever change a value and want something to happen with that change, you will make a function to be called for it. For example:
local Time = 0 function ChangeTime(val) Time = val print("Time Changed") end
so instead of saying Time =
whatever value, you say ChangeTime(whatever value)