This is such a fun way and REAL WORLD example as to why students need to know how to subtract decimals. My students love this activity and would actually consider it more than a game than math practice.
All you need to complete this activity in your classroom would be menus from a favorite place to eat. Many restaurants have (To-Go) paper menus. I love using the "real" menus because it makes it more authentic. You can also just print off menus from restaurants websites. I have used Red Robin's menu in the past below is the link to the menu.
Students can work in pairs or on their own. These is a wonderful worksheet that works as a graphic organizer to help guide and organize their thinking and work. At the end of class students love to share what they and a friend will be eating.
I have created this to where it scaffolds the students learning so don't forget to remind the students to bring down the decimals when needed.
Number and Operations in Base Ten
Perform operations with multi-digit whole numbers and with decimals to the hundredths.