A complete learning trial occurs when a naturally-occurring or planned antecedent is followed by a behavior that leads to a naturally-occurring or planned consequence.

By antecedent, we mean something that sets the occasion for a child's behavior. Antecedents are "cues" for the child indicating which behaviors are appropriate or desired at particular times or in particular settings. For example, during an art activity a teacher may place the paint just out of reach for the child so as to set up an opportunity for requesting.
By behavior, we mean something the child does following the antecedent. Behaviors are things that can be seen, heard, or felt. Behaviors are measurable. Following our example, the child will need to ask for the paint.
By consequence, we mean something that happens in the child's environment immediately following his/her behavior. In this example, the child would be passed the paint and able to begin the activity.

Antecedents and consequences can be naturally-occurring or planned. By naturally-occurring, we mean something that typically occurs in the child's environment. By planned, we mean something that the teacher or other adult has done to encourage a behavior that would not otherwise have occurred. In our example above the antecedent was planned and naturally-occurring and the consequence was naturally-occurring.

Complete learning trials occur whenever there is a "complete" A-B-C sequence. Anytime there is an A, but no B, or a B but no C, or a B that does not follow logically from an A, an INCOMPLETE learning trial has occurred.

We know from research that complete learning trials are important for early learning, particularly for children with disabilities. Specifically, instructional procedures (whether they be universal curricular modifications, targeted currciular modifications, naturalistic instructional procedures, or specific instructional strategies) are effective when they result in complete learning trials for the child.

Complete learning trials can be embedded in ongoing [naturally-occurring] activities, routines, and transitions in the classroom. Complete learning trials can be massed together or distributed based on the needs of the child, the learning target, and the context of the instruction. Whether complete learning trials are distributed or massed the instructional trials should occur in a context that is meaningful for the individual child.