  This article describes the MyST corpus developed as part of the My Science
Tutor project -- one of the largest collections of children's conversational
speech comprising approximately 400 hours, spanning some 230K utterances across
about 10.5K virtual tutor sessions by around 1.3K third, fourth and fifth grade
students. 100K of all utterances have been transcribed thus far. The corpus is
freely available (https://myst.cemantix.org) for non-commercial use using a
creative commons license. It is also available for commercial use
(https://boulderlearning.com/resources/myst-corpus/). To date, ten
organizations have licensed the corpus for commercial use, and approximately 40
university and other not-for-profit research groups have downloaded the corpus.
It is our hope that the corpus can be used to improve automatic speech
recognition algorithms, build and evaluate conversational AI agents for
education, and together help accelerate development of multimodal applications
to improve children's excitement and learning about science, and help them
learn remotely.
