I can't believe no one has mentioned Press Gang.
That was the best.
Three things about Press Gang firstly was the quality of the cast, all of the main characters have gone on to have successful acting careers.
The second and probably the biggest reason was the budget of Children's TV at that time .This allowed Central TV to dedicate the same amount of time and money on Press Gang as many high budget adult dramas at the time.
Thirdly Press Gang never treated 'Children' as children when presenting serious issues . This is great credit to Stephen Moffat . The best Children's television shows actually become 'entertainment' for everybody and not determined by 10-16 year age demographics.
All in all probably the best children's television ever produced in the United Kingdom.
I do though want to mention Educating Marmalade and the brilliant and sadly missed Charlotte Coleman. An all round brilliant talent.