A study found that the instructional design (pedagogical structure) of AI tutors significantly boosts student learning, but the interaction method (voice vs. text) does not affect learning outcomes, even if voice is preferred.

In plain terms

AI tutors are becoming common, but we don't know how best to design them for student learning, especially regarding *pedagogical structure* (how the AI teaches, like guided questions) and *interaction modality* (how students talk to it, like voice or text). Researchers experimented with 86 graduate students, comparing a *structured AI tutor* designed to guide learning based on course materials against a control group with general AI access. Within the structured group, students alternated weekly between voice and text interaction with the tutor. They found that the structured AI tutor significantly boosted learning, with tutored students scoring 6.63 points higher and showing improved written reasoning. However, interaction modality (voice vs. text) had no impact on learning outcomes, despite voice being preferred and more costly to deliver. This suggests that the "how" an AI teaches (pedagogical structure) is vital for learning, not just making it seem more humanlike through voice.