Hi Singmee,
It sounds to me like you are doing a great job if your parents are "wowing" you. The other leaders probably asked each of boys to bring some craft supplies or something to that effect.
As for the Bear Book...
There is 4 sections in the book (God, Country, Family and Self) with a total of 24 requirements. In order for a boy to earn his rank he must complete the following # of achievements in each section...God 1 of the 2), Country 3 of the 5, Family 4 of the 6, Self 4 of the 11. Any additional achievements they finish counts towards Arrow Points. It takes 10 achievements for 1 Gold/Silver Arrow Point. The first 10 are for the Gold Arrow Point (only one can be earned per rank), the others will count towards Silver Arrow Points.
Our dens incorporate the theme and achievements together. In other words they do a craft that has to do with the theme but would also count for an achievement or arrow point.
As for a time range on completing a rank, as long as they complete it before the end of the school year.
I hope this helps.
Good Luck!