“Spaced repetition” for learning japanese

So having been grounded at home since yesterday evening with high fevers… I had to cancel my japanese class today :( since anyways I can not really concentrate on anything. So, instead of my usual rehearsal for japanese, I’ve been wandering internet and stumbled upon this Spaced repetition term… now the sound of that page is somehow too good to be true, but maybe it works? I dunno, would have to spend a bit of time researching it before I commit to really using it for my japanese learning, although most probably it’s better than my random “i wanna rehearse that today” system ^_^