Thanks for all your quick answers.
I use regularly embedded GeoneXt applets in Moodle lessons.
The example given by Furio Petrossi seems to be of the same kind : a Geogebra applet as an illustration in a lesson inside a SCORM package.
But, I would like to try to duplicate the exercices shown in the examples above : the student make a construction in the applet and a feedback on his construction would be given by Moodle.
Thanks again for your interest,