Bible memorization is not something to do to the time pass. The idea of creation of the universe and glorifying God can be too much for a child to fully understand. It's important to teach a child to appreciate the importance of the early Bible memorization.
In any case, it is not possible to teach a child to memorize the Bible little by little. Difficult, but not impossible. You can get more information about the chronology of the bible via internet sources. In fact, here are some tips on how to do make children memorize the bible:
Delete the words one by one
Writing complete Bible verses on a piece of paper and have the children read out loud a few times. Then remove the word and have him repeat the verse, loud. Keep doing this, delete the words as you go along, and the child would have to memorize verses by heart.
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The steps to memorize
Traced the outline of your foot on a piece of paper and then cut it. Write one word of a Bible verse on it, creating a lot of "footprints" are required to complete the entire paragraph. Tape footprints on the floor and have their children move while reading the words written on the site. This kind of exercise will help his memory later when he tried to remember all the Bible verses from memory.
There are several different ways to teach children to memorize the Bible. It is not limited to just two. There is this thing called Memory Verse Bible and Bible Word Scramble Relay, etc. Each of the effectiveness of this method depends on the ability and willingness to teach children to learn, of course.