Input to the ALEKS system is always in the form of proper expressions and constructions , never multiple choice. A critical reason for this is to check students' knowledge accurately.

The general term for the input tools used in ALEKS is the "Answer Editor." This encompasses a variety of actual modes for user input corresponding to numerous forms of chemical and mathematical representations. A student beginning to use ALEKS is trained in how to use the features of the Answer Editor that are relevant to the subject (Sec. 3.8).

In much of what follows in the tutorial, emphasis is on the "Answer Editor for Chemistry," including its specialized facilities for Chemical expressions and representations.