When using the Collapse-O-Matic plugin to create expandable content containers on your WordPress pages, you can optionally specify the HTML tag that is used for the expandable section title. By default Collapse-o-Matic will render titles using a span tag. But, for more control, you can use other tags:
H2 Tag Container
This is the container content.
H3 Tag Container
This is the container content.
H4 Tag Container
This is the container content.