Hand position? What do you mean?
Students come to lessons with varying abilities and hand strength (duh Emily!) but when they play, students NEED to have a good strong hand to do cool things on the piano. But when you hear the words, Strong Hand Position, do your eyes roll back? What does it even MEAN?
My favourite tool is the Hutchinson checklist in exercise 1 of his book of activities.
Sit at the piano and put your hands on the piano. Check your arms - are they bent with a V? If so you are too close and you need to move your bum back. You should have a reclining L - almost an I but not quite.
Then curl your hand like you are cupping a ball or something very fragile and put your hand on the piano.
Are your fingers flat? Shift them so you are playing on the finger tips!
Check your wrist! Is it low? Lift it up (you should be able to not see your finger nails!) and pitch it out toward the outer part of the piano.
Check your baby finger!! Is it collapsing under your hand? Make sure to lift it up and rest your finger tip on the key!
What about your shoulders? Are they tense and almost touching your ears? Relax them!
Try playing like this and see what results you get!