Proceedings 9th International Workshop on Theorem Proving Components for Educational Software

The 9th International Workshop on Theorem-Proving Components for Educational Software (ThEdu20) was scheduled to happen on June 29 as a satellite of the IJCAR-FSCD 2020 joint meeting, in Paris. The COVID-19 pandemic came by surprise, though, and the main conference was virtualised. Fearing that an online meeting would not allow our community to fully reproduce the usual face-to-face networking opportunities of the ThEdu initiative, the Steering Committee of ThEdu decided to cancel our workshop. Given that many of us had already planned and worked for that moment, we decided that ThEdu20 could still live in the form of an EPTCS volume. The EPTCS concurred with us, recognising this very singular situation, and accepted our proposal of organising a special issue with papers submitted to ThEdu20. An open call for papers was then issued, and attracted five submissions, all of which have been accepted by our reviewers, who produced three careful reports on each of the contributions. The resulting revised papers are collected in the present volume. We, the volume editors, hope that this collection of papers will help further promoting the development of theorem-proving-based software, and that it will collaborate to improve the mutual understanding between computer mathematicians and stakeholders in education. With some luck, we would actually expect that the very special circumstances set up by the worst sanitary crisis in a century will happen to reinforce the need for the application of certified components and of verification methods for the production of educational software that would be available even when the traditional on-site learning experiences turn out not to be recommendable.