Shakesperean tragedies are timeless and popular classics because their themes are universal - they speak to us all about themes that afffect everyone right down through the ages because they deal with human lives and emotions. Some are concerned with the young ( Hamlet, Romeo and Juliet) but King Lear is different because it is a tragedy dealing with the sadness and inevitability of aging. It tells about a time when a father must let go control and cede 'power' to his children. It is a happy situation if a family have been loved nurtured and supported and the young still adore and respect their elders, but things don't always work out like that. Sometimes, that power is gained through exploitation of need and incapacity or through force . But however the children acquire it, it is still a painful journey for a proud and independent man to make, but death and old age come to us all and Shakespeare deals with that in this play. It is also about dependency more generally for Lear has little choice but to acquiesce and it even says in the bible that when we are old we must be taken by the hand and taken where we do not wish to go - the inevitability of this feels tragic to us all. There is also a warning in there somewhere from Shakespeare that may be worth your teasing out - a suggestion that we reap what we sow and fathers must remember that their main roe is to love, protect and nurture their children - for one day they will depend on them for everything even if that is choosing the safest social care.