This volume constitutes the papers of two workshops which were held in conjunction with the 21st International Workshop on Software Engineering and Formal Methods, SEFM 2023 Collocated Workshops, held in Eindhoven, The Netherlands, on November 6–10, 2023The 10 full papers presented in this book were carefully reviewed and selected from 16 submissions. SEFM 2023 Collocated Workshops presents the following two workshops: 5th International Workshop on Cognition: Interdisciplinary Foundations, Models and Applications (CIFMA 2023)11th International Workshop on Open Community approaches to Education, Research and Technology (OpenCERT 2023)