How do you discard a card in wizard101 on mac?

To discard a card in Wizard101 on a Mac, open your spell deck by clicking on the deck icon. Select the card you want to discard by clicking on it, then press the "Delete" key on your keyboard. Confirm the action if prompted, and the card will be removed from your deck. Alternatively, you can drag the card to the trash can icon in your deck interface.