This short course on IRT was implemented in learnr by a group of students at the Glasgow meeting 2018 and then extended by KULeuven.
This course contains a learnr tutorial and a Shiny app using urn problems to illustrate different probability distributions. The learnr tutorial was implemented by a group of students at the TquanT Glasgow Seminar 2018, the app was implemented by University of Tübingen based on the learnr tutorial. However, it has a slightly different selection of probability distributions and it includes some test for your knowledge learned in tutorial and app.