Colour-coded German textbooks to aid learning

Here's an example of how a colour-coded German textbook could work to aid the student in learning the gender of a word, given that it is usually impossible to identify the gender from the appearance of the word alone (Bulgarian, Spanish, Lithuanian, Latin etc. usually give much more obvious clues as to the gender of a word):

Wikipedia ist ein Projekt zum Aufbau einer Enzyklopädie aus freien Inhalten in allen Sprachen der Welt. Jeder kann mit seinem Wissen beitragen. Seit Mai 2001 sind so 976.529 Artikel in deutscher Sprache entstanden. Gute Autorinnen und Autoren sind stets willkommen.

(blue=masculine, pink=feminine, grey=neuter)

The vocabulary list could also be organized in a similar way, even perhaps with the article stuck right on to the word in order to make it harder to gloss over. This is similar to a tip I've seen for Bulgarian where the gender is easier to keep in mind if it is stuck right on the end of the word, thus remembering the word as lunata for moon (the moon) instead of luna.

derArtikel 

derAufbau  
derAutor

dieAutorin

dieEnzyklopädie  
derInhalt 
derMai  
dasProjekt
dieSprache

dieWelt

dasWissen

In addition to this another way to identify the case could also be a good idea, perhaps with something like an arrow under the word for the dative, one going down for the accusative (symbolizing the motion involved in taking or handling something), and something like <--> for the genitive. Here are a few examples with just the cases marked (colour for the gender would also be marked on top of this of course).