Preheat oven to 375°F (190°C).

Cream together margarine and brown sugar until light and fluffy.

Add vanilla and eggs, and beat well.

In a separate bowl, mix together whole wheat flour, wheat bran, and baking soda.

Gradually add the dry mixture to the wet ingredients, alternating with water.

Beat until well combined.

Stir in chocolate chips.

Drop by spoonfuls onto ungreased baking sheet.

Bake for 8 minutes, or until golden brown.