What will make this text button change texts?

I need it so that when the player clicks the text button, the text of it goes from "High", to "Low" and this script isn't working. There is a blue line under the word "Low". I am new to scripting and still learning so try to make it understandable for a newbie :D

script.Parent.MouseButton1Down:connect(function()
	script.Parent.Text = Low
end)

The reason the text isn't changing is because you are giving it a variable to change to, you want to change it to a string

script.Parent.MouseButton1Down:connect(function()
    script.Parent.Text = "Low"
end)

Strings are made using " " or ' '

You can create a variable with a string value then use it to change the text of the button

local text = "Low"
script.Parent.MouseButton1Down:connect(function()
    script.Parent.Text = text
end)