This exercise rocks!
It was created by French pianist and composer
en.wikipedia.org/wiki/Charles-Louis_Hanon
Once it was time, when most piano schools followed them religiously. I found it very beneficial for any beginners to start with the First exercise. I had students as young as 2 year old being able to play it. Besides all the educational benefits, this exercise is bringing awareness of each finger and coordinates all of them. It helps to build more pathways in corpus callosum – a bridge between right and left hemispheres.
I would recommend to play Hanon 1 in following steps:
1. Beginning – just try to play with separate and both hands
2. When comfortable, say/sing the notes played.
3. Play with metronome or build-in rhythmical accompaniment
4. Little by little increase the speed with metronome
5. Little by little play more octaves
Here is some helping video, where I teach 3-year-old girl to play Hannon #1