Dinghy sailing in bigger winds

Hey chaps/chapesses

My two sons sail/race Cadets and, being light (50kgs+23kgs) struggle
badly in the bigger winds (f4+).  I don't have the expertise to guide
them but I believe it is as much a matter of technique as weight.

So far I have (a) rake the mast back (b) de-power the sails with
cunningham/outhaul/kicker (c) sit further back on a run, lifting the
bow.

So what am I missing?  I seem to think that pointing up or bearing
away when a gust comes has a bearing on this.  I also seem to think
there are better techniques of easing the sails than just letting go.

What else can we do?

Is there a good book to read that will guide us through?  Is there a
training video we can watch?

Thanks in advance for any help/advice you can give us.

Stephen Page