BlockTalk

https://blocktalk.gse.harvard.edu/

How can K-12 computer science teachers develop their skills in supporting student debugging without the pressure of real-time classroom interactions? BlockTalk is a generative AI-powered platform that offers an environment for teachers to practice and reflect on their debugging instruction strategies.

Drawing on research about common Scratch programming errors and central computational concepts, the platform presents teachers with AI simulations of fifth-grade students working on Scratch projects and encountering programming challenges, from missing broadcast blocks to incorrectly nested loops. Teachers can engage in conversations with these AI students, practicing different approaches to guiding learners through debugging processes.

Released in October 2024, BlockTalk is free and available to the public. We invite you to watch this video introduction to BlockTalk and try out the simulations on the BlockTalk website.

Additional Readings and Resources

How Generative AI Can Support Professional Learning for Teachers, HGSE Usable Knowledge article from October 2024 about the launch of BlockTalk
Haduong, P., Yu, B., Shen, M., Gerami, B., & Brennan, K. (2025). BlockTalk: GenAI simulations for conversational debugging practice. In A. Rajala, A. Cortez, R. Hofmann, A. Jornet, H. Lotz-Sisitka, L. & Markauskaite (Eds.), Proceedings of the 18th International Conference of the Learning Sciences - ICLS 2025 (pp. 2852–2854). https://doi.org/10.22318/icls2025.459142

This work was made possible with support from the Scratch Foundation and the Harvard Generative AI Research Program from the Office of the Vice Provost for Research and the Office of Undergraduate Research and Fellowships.