Sweet. Target takes 50% off Casper Sleep Sheet Sets when you clip the 50% off Target Circle Coupon! It looks like prices are as low as $37 which is awesome! All sizes from twin to California king are available. Most sets will include 1 Pillowcase, 1 Flat Sheet, 1 Fitted Sheet. Plus, use your Target REDcard to save an additional 5% off and score FREE shipping.