Trying to do Free Shipping on certain products

Hey Everyone -
I am going to be offering a special for the rest of this month of free shipping on collars, leads, & toys. I am confused on how to do this though since my shipping is set up as flat rate depending on the amount of the sale. If I go into each product individually and set it to "Always free shipping" will the checkout read that correctly and not count that dollar amount into the shipping amount?
If not, what should I do???

Any help would be greatly appreciated!
Thanks so much!
Tiffany
Owner/Trainer
The Furr Factor
http://www.thefurrfactor.com

Always Free Shipping is removed from the item count, or the weight or the order total to calculate the shipping ...

NOTE: because a customer might buy only Product(s) with Always Free Shipping, you will want to set up the Modules ... Shipping ... Free Shipping freeshipper to manage this type of order ...

I set up those modules, then I set one item to ALWAYS FREE SHIPPING. If that product is ordered by itself then it works fine and there is no shipping cost - but, if I add another product that is NOT always free shipping, then, the shopping cart calculates the total of BOTH items and charges shipping on the full amount, not just on the amount of the item that is not free shipping.....???

What version Zen Cart?

What Shipping Modules are installed?