For dropdown options you probably want something like this:
var selectedVal = $('#id_material').find(":selected").text();
The reason val() doesn't do the trick is because clicking an option doesn't change the value of the dropdown--it just adds the :selected property to the selected option which is a child of the dropdown.

For dropdown options you probably want something like this:
var conceptName = $('#aioConceptName').find(":selected").text();
The reason `val()` doesn't do the trick is because clicking an option doesn't change the value of the dropdown--it just adds the `:selected` property to the selected option which is a *child* of the dropdown.