1. A computer-implemented method of providing interactive online sessions for presenting art objects, the method comprising: providing remote access to a user to participate remotely in an online session of a first type; creating the online session of the first type; causing a remote displaying, under control of at least one session leader of the online session of the first type, a number of images of a plurality of art objects to the user during the online session of the first type; electronically receiving an indication of interest of the user to participate in an online session of a second type based on an interest of the user in one of the art objects; creating the online session of the second type; providing remote access to the user to participate remotely, under control of at least one session leader of the online session of the second type, in the online session of the second type that includes as participants the at least one session leader of the online session of the second type and the user; during the session of the second type, receiving a selection of an image of the one of the art objects, the one of the art objects being a physical art object, the physical art object having one of more physical dimensions; receiving a selection of an image of a first reference object, the first reference object being a physical reference object, the physical reference object having one or more physical dimensions; and in response to receiving the selection of the image of the one of the art objects and receiving the selection of the image of the first reference object, electronically causing a displaying in the online session of the second type at least one image that concurrently shows a visual representation of the one of the art objects and a representation of the first reference object in which the visual representation of the one of the art objects and the visual representation of the first reference object are proportionate in size to each other based at least in part on the one or more physical dimensions of the physical art object and the one or more physical dimensions of the physical reference object.