Enforce diacritical marks?
I've noticed so far that if I leave off accents and umlauts that I'm not penalized for this. Is there a setting I've forgotten about to mark me wrong if I don't use them?
This is an infinitely recurring question on Duolingo. I think the consensus is that while people generally want to learn the language accents and all, the fact that most English speaking users are going to be stuck with a QWERTY keyboard makes it impossibly unfair to enforce their usage, without frustrating vast amounts of people. Compared with the freedom of pen and paper, the humble keyboard is practically a straight-jacket to the art or writing. To that end, Duolingo constantly reminds you that they are there, but turns a blind eye when you don't use them - though there are also many substitutes it accepts, for example I know for Danish 'ae' is always accepted in place of 'æ', and for German the pretty much standard 'ae' 'ue' 'oe' substitutions can be used, and who can really complain about that?
It's easy to feel that the written standard of any language is precious, but that flies in the face of the fact that the way languages like English and French are spoken has barely any connection at all to the way they are written, and this doesn't seem to trouble us in the slightest. We seem to be able to handle this disconnect between writing and speech quite well in our own language, so why should it be different for any other?
My frank opinion, it doesn't matter if you can type the special characters or not. If you are consciously aware that you should be typing something else when you use 'a' instead of 'å', then you are already internalising the difference, which is the only important thing. Stop using the computer for two seconds and pick up a pencil, and you'll realise you have no trouble at all with proper spelling. If you want to mail order a Swedish keyboard (or just change your keyboard layout and put sticky labels on the one you have), great, but going through that rigmarole shouldn't be the price of admission for everyone.