Interfaces facilitate the teaching of hydrological modeling tools, which can otherwise be slowed down by the difficulty for students or water managers to manipulate data or models. To solve these problems, the Hydrology Group at Irstea (Antony) developed an open-source tool using R and proposes a package called airGRteaching (Delaigue et al., 2018) based on lumped rainfall-runoff models that are already included in the R-package airGR (Coron et al, 2017). airGRteaching includes the following features: - three simple functions to prepare data, calibrate a model and run a simulation, - functions producing static and dynamic graphs, - an interface linking airGRteaching to a browser-based visualization tool showing quasi-immediate updating of simulations. In this presentation, we focus on how the graphical user interface (GUI) can be used to apply concepts acquired during courses or trainings. The airGRteaching GUI presents different visualization panels to analyze model simulations using synthetic performance or flow time-series graphs or internal states of the model over time. The visualization panels contain clickable dynamics graphics and are accompanied by a table presenting the values of the efficiency criteria, to criticize the results by combining visual and numerical criteria. Graphs and outputs can be exported to PNG and CSV for reporting. References Coron L., Thirel G., Delaigue O., Perrin C., Andréassian V. (2017). The Suite of Lumped GR Hydrological Models in an R-package, Environmental Modelling & Software, 94, 166-171. dx.doi.org/10.1016/j.envsoft.2017.05.002. Delaigue O., Coron L., Brigode P. (2018). airGRteaching: Teaching Hydrological Modelling with GR (Including a Shiny Interface). R-package version 0.2.3.2. https://CRAN.R-project.org/package=airGRteaching/.