Options:
- Sell them on Ebay. At least you would cover shipping
- Give them away to bloggers. Just send them one with a note about consider blogging about it.
- Give one to Zaine

. He would probably enjoy it and blog about it. (
http://www.thegsblog.com/). The girls better be hot or he will let you know about it.
- My blog / address in case your interested (
http://www.veign.com/blog/)
- Contact some of the mall Calendar Stands to see if they would push it. Sell it to them so they can turn a profit.
If you want some constructive critism then you need to focus on the target market. You're trying to sell a calendar titled Girls of Engineering but you don't show them in a geeky, engineering environment. Therefore you have nothing more than a standard, plain bikini calendar with a different title and the same type of girls in a non-themed layout. If you do it again, really play up the geekiness of it and make the girls sexy in a very geeky / engineering environment. Just my .02.
Good luck.