Hi there, depends which Max Planck Institut, there are various ones specialising in different fields of research and I don't know where they are all located. The Max-Planck-Gesellschaft for instance is in Dahlem which is a nice leafy green suburb so living round there would be pleasant enough. Your dh may be working somewhere totally different though.
Your ds aged 7 could attend either the British school in Charlottenburg-Neuwestend (nowhere near Dahlem) to keep on track with the NC (Achtung: yearly fees around 15,000 Euros and all the extras) but he would get in no problem because classes are small, school day is 9-3pm, uniform etc. Or you could go for the International School just outside Berlin - BBIS - Berlin-Brandenburg International. Same kind of fee structure, good facilities, follows the Int Bac curriculum.
If you want to try a bilingual option, he may fall behind v.a.v. the British curriculum because school starts later in Germany (aged 6 and the bilingual schools do not rocket ahead IME). As options you have the American-German John-F-Kennedy School in Zehlendorf (so near Dahlem). I hear good and bad. They do have better facilties than the regular German schools and an active parental involvement, lots of afternoon activities on offer. They cater for people coming and going with little or no German BUT they essentially want only German or American families. Apply from outside, directly to the head of Elementary (and bypass the secretary if at all possible) and see what they say if that interests you. Will be practically impossible for you to get in if you apply when you are in Germany since you are not American.
There are also so-called Europa schools. These are state-run bilingual schools. For English there is the Quentin-Blake in Zehlendorf, not far from the JFK. In Charlottenburg- Neuwestend the Charles Dickens (shares playgroudn with the British School) and the Nelson Mandela centrally in Wilmersdorf. Apply from overseas. They will all take your ds because they generally don't have enough English speakers. Same problem here, essentially they are behind the ENC because of the later start, they are not phenominally academic but I find nicer than the standard German schools. THey are in theory free but you do have to pay for various things, however it doesn't break the bank. The dc in the English language streams have English together (small class) whilst the German stream has German, then they swop. THe whole class does maths (in German), art , PE etc together. School day is long - 8-4pm compulsory which includes scheduled play-time under the supervision of a carer (sort of trained nursery worker). The grounds are generally better than your standard German school (exception being Nelson Mandela) because they were built as schools for the English/American military in the past, so different concept of what a school has to look like.
There are a few other bilingual options, schools recently opened by frustrated parents etc. I think for you they aren't a reasonable option. They are geared towards promoting language skills of German dc.
Is that any help? To summarise:
Expensive and English only (but I think good)
- British School (prob best but classes can be very small)
- BBIS international (IB not ENC)
- JFK (German-Am you may not get in)
4 Europa schools Quentin Blake (Dahlem)
- Charles Dickens (Charlottenburg)
- Nelson Mandela (Wilmersdorf)
There are bilingual nurseries and the British school has a preschool. If you can afford it , I would send your ds there - or keep him at home if he has language problems atm.