If you want to give out your decks for free as samples, as promotional materials, or just out of the goodness of your heart, go for it! You get to set the prices for anything and everything you sell, and you can post them for free either temporarily or forever.
Offering a Free Deck
Sellers are encouraged to make some of their materials free. People are much more likely to look at your store if they sample free products from you and like them. This is especially true of new users.
Anyone with a Boom Learning account can “buy” a free deck, and they get to keep it forever - even if you later raise the price.
Offering a Sale Price
If you want to have a short term sale, first announce the terms of the sale. You can make this announcement using whatever means you use to reach your buyers (blog, social media, etc.). We do not currently have a way to show the prior price, so you'll need to announce the percentage off to make potential buyers aware of the reduction in price.
Next, you will need to manually open the product and change the price in the details in time for the sale's launch. When the sale is over, you'll need to go back in to change it back to the original price.
If someone adds an item from your store to their cart while it is offered at a reduced price (including 0 points), they can check out at any time without it impacting the price. This can throw some sellers the first time they see a deck sell for less than the current list price.