Abstract: Techniques performed by a data processing system for facilitating an online presentation session include establishing the session for a first computing device of a presenter and a plurality of second computing devices of a plurality of participants, receiving a set of first media streams comprising presentation content from the first computing device, sending a set of second media streams to the plurality of second computing devices, receiving a set of third media streams from the computing devices of a first subset of the plurality of participants including video content of first subset of the participants captured by the respective computing devices of the first subset of participants, analyzing the set of third media streams to identify a set of first reactions by the first subset participants to obtain first reaction information, determining first graphical representation information representing the first reaction information, and sending a fourth media stream to cause the first computing device to displ