Hello Oasis,
I think the reason people hesitate to answer you is because there’s not really any precise answer to your question.
If you were to collect a big list of items, like all ShenLi’s Dinosaurs for instance, the simplest way would be to create your own category and select 10 dinosaur slides for the category. You can play that same category 3x day, 10 days in a row, and then replace one everyday from then on in. You could then start adding facts to the slides you are abandoning, so instead of them saying “Tyrannosaurus” you could have the slide say, “Tyrannosauruses were the biggest meat-eaters.”, make 10 of the fact slides and start playing that in addition to the original plan. (Once you start abandoning them, start adding the next fact, until you get to 10, as per Doman.)
This whole system get tricky fast, and on top of that, your little one might think that 30 repeats is a bit “overkill”, so that’s where the course builder comes in. It might take you some time to figure it out, but I would like to encourage you to start playing with the course builder because it makes your life so much easier. When you find out your little one wants to speed the learning process up, you can adjust the course you’ve build in a minute for less repeats, more/less slides per lesson etc.
The big job is to collect facts, the library has tons of slides, but not a lot of facts. The reason is because this is a lot of work. Easy to create 100 slides of some category, it gets harder when you want to add 1000 facts to them. BUT, working as a team, this is becoming a reality, as you will soon see with the country course.
The length of a lesson will depend on your little one. For me, mine went through stages, sometimes he’ll watch many, other times he will not. When you find a long list in the library, chances are they’re not suppose to be used in one sitting. Now after 2 years of flashing, W can sit through long lessons, but then it’s not likely he’ll ask for it everyday. Short lessons (6 or 8 flash cards per type) still works best, but then we watch different courses back to back, with some flashing mixed with stories, videos and slow paced facts. Some days we’ll do long hour long sessions in front of the PC, other days we’ll split the session up in 3 or 4 small sessions, and then others we don’t even come close to the PC.
The sooner you start trying it out and playing with ideas with your little one, the sooner you’ll figure out what works best for you and your boy. The only “hint” I really want to stress is to start very small, he might sit and watch long lessons initially, but you don’t want him to grow tired of it at any stage, because then he might not sit for even the shortest lesson.
Good luck!