Learn the Dutch Genders in One Day!*
The secret to learning the Dutch grammatical genders amazingly fast is to focus on learning just neuter words with one syllable- there are about two hundred of them in common use. The genders of more than 90% of all other Dutch nouns can then be determined by what sort of things they are, or by their beginnings or endings.
To learn the 200 neuter monosyllable words easily, just add "O" (for Australia) to the beginning of each of the words and use the following "O-pictionary" pictures to lock the words in your memory.
*The caveat to this plan is that it does require that you recognize if a word is a noun, know approximately what the noun means, and know if it is derived from a verb or an adjective. Knowing English is a big help because many words are the same in both languages, including about half the "O-words"!