Plugins: Collapse-o-matic

What it is: “Collapse-O-Matic adds an [expand title="trigger text"]hidden content[/expand]shortcode that will wrap any content, including other shortcodes, into a lovely jQuery expanding and collapsing div. A complete listing of shortcode options and attribute demos are available, as well as free community support.”

Example:

More info: https://wordpress.org/plugins/jquery-collapse-o-matic/