You can see here >> https://www.odoo.com/documentation/functional/valuation.html how costing methods works in Odoo.    

Hi,

If you are looking to compute the standard price from materials in the product BoM & work centers with accounting entries, you may try this:

https://www.odoo.com/apps/modules/8.0/product_extended/

After installing the module, you need to set the costing method in the product as Standard Price. Then it will give you a button "Recompute price from BoM" under cost price field in product form like this.