PlayTops is one of the first research projects to investigate the use of laptop ensembles in Early Childhood Music Education. The project contributes to the latest developments in embodied learning by exploring modular digital instrument design for supporting the basic mechanisms of musical sense-making (i.e., alignment, entrainment, and prediction; Leman, 2016) and, as such, embodied music learning (Nijs & Bremmer, 2019). The project goes beyond the physicality of the laptop, transforming “LAPtops” into “PLAYtops” through an Internet of Things (IoT) network of physical sensor-containing objects (PlayTops units) connected to a laptop allowing students to play the computer like a musical instrument. While the latest musicological insights on embodied human interaction with music, i.e., discerning the basic mechanisms of musical sense-making, have been translated by Nijs and Bremmer (2019, 2020, 2022) into an Embodied Music Pedagogy, empirical investigation addressing these basic mechanisms in education is undertaken by this project. An important – and innovative – aspect of the project is the implementation of this operationalization through sensor-based qualitative measurement of bodily engagement in music-making and learning. The project investigates the learning potential of laptop ensembles incorporating play-based modular multi-modal sensor instruments through a quasi-experimental pre- and post- test group design involving three groups (3 x n=min 10) of children aged six to seven (basic school cycle two), comparing the use of a modular version of PlayTops (Group A) and a non-modular version (Group B) to a control group (Group C), following regular music classes at a school in Luxembourg. Data collection involves qualitative (questionnaire, interview, video) and quantitative (e.g., sensor data, standardized music perception, and production test) measurements.