Playpen: An Environment for Exploring Learning Through Conversational Interaction. - Nicola Horst; Davide Mazzaccara; Antonia Schmidt; Michael Sullivan; Filippo Momentè; Luca Franceschetti; Philipp Sadler; Sherzod Hakimov; Alberto Testoni; Raffaella Bernardi; Raquel Fernández; Alexander Koller; et al. (CoRR, 2025)