Unfortunately, the default shipping options in Shopify don’t allow for free delivery on only a certain item or collection type. To do this, you will need a third-party shipping calculation app.
My husband and I created Intuitive Shipping, which along with a ton of other features, can offer free shipping on certain items or collections. We offer a free 14-day live trial, so you can take it for a test drive in your store. Intuitive Shipping defaults to ‘testing mode’, which gives you time to get your rates set up and test your scenarios out (using customer name ‘Intuitive Shipping’) before you make your rates visible to your customers. Once you turn testing mode off, live mode starts, making your rates visible to your customers and your 14-day trial period will begin.
Please reach out at firstname.lastname@example.org if you have any questions.
I suppose our Free Shipping & Hello Bar app allows you to do this.
It's fully Customizable notification bar to promote Free Shipping, Free Gifts or just inform your customers about something.
I think what Levi is looking for is the ability to set certain products and collections to not charge shipping at checkout, and to charge for everything else in the cart accordingly. Your app is good for promoting the promo, though! :)