My grandparents were all taught both English and German languages as young children.

Mum's parents, Carl Wilhelm Traugott Tschirpig and Anna Maria Elisabeth Milich (both the second Australian-born generation) seem to have inherited a preference for German as the language to speak around the home.  Mum told me that they would usually speak to her in German, and she would reply in English.  There seems to have been no effort to formally educate Mum in German language, and she had no further contact with it after leaving her parents' home.

Dad's parents, Bernhardt Herbert Vogt and Mathilda Louisa Engel were very much younger than Mum's parents, so I was able to have lengthy conversations with them during the 1980s.  Both had attended bilingual Lutheran schools.
Around 1903-1906, my grandmother, her younger sister Minna and her older brother Carl attended Martin Luther School (an arm of Bethlehem Lutheran Church) in Flinders Street, Adelaide.  She also attended reunions in 1949 and 1983.  Her parents were both born in the newly integrated Germany (mother migrated in 1883, aged almost 6; father migrated in 1895, aged 22), so it's not surprising that German was their preferred language.  In particular, her father (musician Karl Engel) hadn't long been in Australia, and had trouble understanding his children when they spoke English.  The children learnt both German and English at school, but seem to have preferred English for themselves.

Dad's father attended the Allen's Creek Lutheran School, on the Tarnma Road, near the Kapunda to Hamilton road.  I have 2 of his exercise books – one from 1906 (grammar and history – excerpts shown below), and the other from 1907 (letter writing practice).  He was the second Australian-born generation, and English was the normal language at home.

World War 1 had serious consequences for German migrants and their descendants.  There was informal persecution – Dad's mother worked as a restaurant waitress in the city of Adelaide, and was challenged by work colleagues who threatened to go on strike unless she was sacked.  My grandmother was a hard worker.  (A patron, Sir Sidney Kidman once gave her a pair of kid leather gloves to express his thanks).  The manageress stood up firmly for her best worker, and the conflict quickly dissipated.  Legislative changes also persecuted the Germans.  The "Education Act Amendment Act – 1916" included these :

1. Section 53 of the original Act was replaced with "(1) All instruction given in any school shall be given through the medium of the English language."
2. Section 3 of the Amendment Act specified that all schools named in The Schedule were to be closed.  Martin Luther School and the Allen's Creek school were at the top of the list.

In 1914, Mum's father was charged with attempting to murder the local policeman (who had made a habit of harrassing and imprisoning "German" types).  The charge was thrown out of court, and the policeman was forced to find some other way of expressing his patriotism.  Circumstances surrounding this were partly uncovered by the Hewitson Royal Commission in 1919.

Now to me.  My lifetime has overlapped with that of only one migrant ancestor – Karl Engel, who died when I was only 2 years old.  I never knew him.  There are no family stories of what the homeland was like, because my parents never heard any.  (Most of the migrations occurred by 1855).  Mum and Dad didn't raise me with any significant knowledge and understanding of my German ancestry, and foreign languages were not taught at Kapunda High School during my time there.  My early impressions of German people were from the TV – they were the ones who lost World War 2, just 20 years earlier.  "Hogan's Heroes" was intended to make German people look stupid – a point that Jewish actor Werner Klemperer insisted on for his character Colonel Klink.  (He had fled with his parents from Nazi Germany in 1933).  In fact, all of the "German" characters in Hogan's Heroes were played by German-speaking Jews who had fled in the 1930s from various central Europe nations to the USA.  The TV programmes "Combat" and "Rat Patrol" depicted the American forces fighting successfully against the "Gerries," so that's what we copied in our childhood games.
It was only through family reunions that I eventually became aware of my ancestry.  (My tribes migrated long before the advent of Nazism and Communism that were to severely afflict Germany from 1933 to 1989). During the early 1980s I started to take a vague interest in learning German language without knowing where to start, and late in 1986 I attended an 8 lesson course at the WEA – "German For Fun and Travel".  Two and a half years later (1989) I took the same course again, although with a different teacher with a different regional accent.
In August-September 1990 I made my first visit to Germany – 2 guided bus tours.  It was intended to be my reconnasance mission in preparation for a free-ranging residential visit a few years later.  At the time, I was working for the S.A. Public Service, who unfortunately didn't have a worker exchange programme.
That all changed in 1996 when I transferred (along with my outsourced work) to EDS.  After lengthy negotiations, in 1998 I was able to get 2 work assignments in Germany –

• A 7-week assignment at the Deutsche Bank data centre in Eschborn (near Frankfurt).  Suddenly moving to the other side of the world is stressful enough, but I was shocked to find the desktop computer (IBM PS/2) working in German language!  I'd assumed that all computers worked primarily in English.  Pocket dictionary to the rescue!  The bank's System Programmers (a very well organised crew) were kind enough to speak to me in English.  One lady claimed that she couldn't speak English, but her team leader later said to me "she needs to read the documentation" (from IBM, which is all in English).
• After a brief visit back to Adelaide, I commenced an 18-month asignment at the EDS data centre in Rüsselsheim.  They already had a colleague from Sydney on a short term assignment, so our team meetings were in English for a month or 2.  After that, I was the only foreigner, and they reverted to German language for the sake of one team member who was originally from Halle (in the east, where the communist government promoted Russian rather than English as a second language in schools).  All of the other colleagues spoke to me in English, so I felt reasonbly comfortable.  Actually, too comfortable.  It soon occurred to me that I should be learning German language from these guys, but that's more easily said than done.  After several months, I found an ideal opportunity to get some professional tuition from one of my friends at the church.
  It was during this period (particularly August 1999 and April 2000) that I had major success researching Dad's genealogy in the church books in Parchen, Hohenseeden and Güsen (Sachsen-Anhalt state).  In the east, some people still don't know any English language, so I prepared myself by learning the vocabulary for it.
  Dealing with people in government offices is usually a troublesome exercise.  It seems that they all went to the type of secondary school where English wasn't a compulsory language.

For general information about Mum's ancestry, visit my Tschirpig web pages.