Cousins, a former director of the Edinburgh International Film Festival, spoke of the plans as he was unveiled as a new honorary professor of film at Glasgow University.
The film maker, based in Edinburgh, has taught at the university before but says that with his new position he will become more visible and available to students at the institution.
He described his new documentary as "a sort of an annexe to The Story of Film", adding: "It's about children in movies, child protagonists in the movies, with loads of emphasis on African, Iranian and Middle Eastern film".
He said: "I want it to be watchable by kids – kids love watching other kids on tele-vision – and will be no more than 90 minutes so children do not get bored. They will be 100 children in it.
"It will be shown on cinema and will be on television as well. It's quite exciting and I think it will have quite an impact.
"Now, after the The Story of Film, people are keener to put this new film out."
Cousins has received awards and plaudits for The Story of Film: An Odyssey, which was presented on television in 15 one-hour chapters.
Produced in Glasgow, it was shown on More4, and in its entirety at the Toronto Inter-national Film Festival and the Museum of Modern Art in New York last year.
The noted documentary-maker Michael Moore described it as "one of the greatest", and a film "we'll be watching all our lives".
It will be broadcast on US television later this year.
"I'm delighted, it's been amazing," Cousins added, "it has sold to 40 countries. It just keeps going and going, and it's so satisfying."
Of his new post at Glasgow University, Cousins said: "It's an attractive thing because I think film-makers like myself should think a bit more, and universities should be more creative, so I think that exchange helps.
"You could argue the best person who ever taught film was Alexander Mackendrick, the great Scottish director, and his book On Film-Making is absolutely brilliant.
"He taught, and his students still talk about him. I've always like the idea there isn't a hard and fixed wall between making, practice and theory."
He said he would not lead "straight lectures" and will be showing students his own films as well as others: this week he showed students a new film called Here Be Dragons that he made in Albania and completed only two weeks ago.
Cousins said he was pleased with the revival in fortunes of Edinburgh's film festival as well as being impressed by the Glasgow Film Festival.
He said: "I went to 35 film festivals last year, I had two films on release, all over the world, and Edinburgh was the best programmed of the lot."