Can anyone help with #game child search?

For future reference, please use Lua code formatting (the little Lua button above the text box on the editor.) when you post code. It makes it easier to see what's code and what's explanation.

It looks like you're trying to make a generic for loop using a numeric for style. This simply doesn't work.

First, pairs is a function, and it takes a Table as an argument. GetChildren returns a Table, but you have to call it as a method, using the : operator.

tostring(v) is unnecessary. print(v) will automatically call tostring() on v, since v is not a string.

Finally, and this is just a stylistic thing, unused return values (i in your code) are typically given an underscore (_) instead of a name, to indicate that they are not used.

for _, v in pairs(game.Lighting:GetChildren()) do 
    print(v)
end --Semicolons are not necessary in Lua 99% of the time.

Pairs takes a table as an arguement, such as the table of contents of Lighting. I think tostring is just for numbers or something. Use v.Name.

for _, v in pairs(game.Lighting:GetChildren()) do
print(v.Name)
end

take away the comma after in pairs and it is :GetChildren() i think you have to add parentheses around #game.Lighting:GetChildren()