I would appreciate it if you would introduce me to some sources of free downloadable videos/films in the French language and French subtitles (either treating of mathematics or of any general subject)
There is an amazing site called Les films français avec sous-titres where one may find a plethora of films to watch of different genres (comedies, dramas, adventures and the like).
Very useful: TEDx chanel in YouTube.
Also: French films with French subtitles in YouTube.
Yet another very useful site cinema-dossier-pedagogique.
Perfect is the enemy of good:-)! I found the following site a most comprehensive source. There is even a classification (B1,B2,C1 and the like):
Hope it helps!
You have also really nice Youtube channels to learn (or improve) french for free among which:
Vincent is a French teacher with his own YouTube channel, and he will teach you thousands of phrases, as well as vocabulary, grammar and the correct pronunciation. He aims to take you from being a beginner in the language all the way to becoming an advanced French speaker. Listening to French is an excellent way of learning, and when viewing Vincent’s videos you can hear him speaking French. Vincent has another website where you can find out all about his services, and he is also offering lessons via Skype.
This site’s slogan is: “Learn French With Us…It’s Fun!” Having fun is always an aid and attraction to learning. The mini-lessons JeFrench offer cover all the basics of the language, and are easy to follow with recognisable images illustrating the subjects covered in their videos.
FrenchPod101 is a very popular YouTube video channel for learning French, and with good reason. FrenchPod101 has a very large selection of videos on so many different subjects that are important if you want a very balanced knowledge of the language. There are videos covering the use of adjectives, there is one that explains three ways of saying you love someone in French, and even a video all about French superstitions. The very slick presentations are in English and French.