How do you count children?

I am trying to figure out how to count how many children (or players) are in a players. Here is something I tried but it didn't work.

function scanclick()
if game.Players.Children < 2 then
	wait(3)
	Instance.new("Part", game.Workspace)
	Part.Anchored = true
	Part.Name = "Not Enough Players"
end
end
game.StarterGui.ScreenGui.Frame.TextButton.MouseButton1Click:connect(scanclick)

You'd use the NumPlayers property of Players. It can be accessed by using game.Players.NumPlayers.Value (Value may not be necessary). The way you were using the GetChildren method was improper, so I stated the easiest way.

Theres a few ways, but this is probably the fastest way:

function scanclick()
Children = game.Players:GetChildren()
if #Children < 2 then
	--Code
end
end
game.StarterGui.ScreenGui.Frame.TextButton.MouseButton1Click:connect(scanclick)