Keth is writing in ON again.
I'll try and respond.

> Heill Haukr!
>
> Ek man skóladagarnir þá vér allr lærðum at benda maðr útan bókar:
> maðr manns manni mann, menn manna mo,nnum menn.

Corrections:

skóladagarnir -> skóladagana (accusative)
allr -> allir (plural)

Glossary:

muna + acc = remember
læra, læri = learn
skóli, skóla, skólar m = school
dagr, dags, dagar m = day
beygja, beygi = decline (MI of course)
útan = without
bók, bókar, boekr f = book
(without book = by heart)

(Your accusative plural of "dagr"
was Faroean there, Keth:)

> Ef konungr bendisk á sama hátt, svo heitir þat:
> konungr konungs konungi konung,
> konungar konunga konungum konunga.

á sama hátt = in the same way

svo -> svá (the first is MI)

> En skip er hvorugkyn (neutrum), ok þat er mik óvissari:
> skip, skips, skipi, skip; skip, skipa, skipom, skip.

hvorugkyn -> hvárugkyn (but the word is MI, of course)
mik -> mér (more unsure _to_ me)
óvissari -> óvissara (it's an adverb)

Your declension is correct although we use
another order for the cases and normalise
to "skipum" rather than "skipom".

> Var þat rétt?

Svá er.

> Ok nú hef ek tilmæli sem nóg mun gjeðast ykkr Óskari vel:
> Ek myndi mjo,k gjarna hafa sét *lectiones* ykkar skrifaðar á
> norr¦nni eða íslenzkri tungu!

gjeðast -> geðjast

tilmæli, tilmælis, tilmæli n = suggestion
gjarna = gladly
hafa sét = have seen
norroen tunga = Norse tongue

It would be a lot of extra work to translate
the course to Icelandic:)

Kveðja,
Haukr