In Query Design, there is an ability to change a field format of text to be all upper case or all lower case. 

1.  Open the Query in Query Design View and select the field you want to change. 
2.  Click Query Tools Design tab.
3.  Located in the Show/Hide Group, click Property Sheet button.
4.  In the Format box, type > to make the text all uppercase or < to make the text lowercase.