
If you'd like to give this a try in your class, here is a link to my instruction and questions Google Slides document and a link to my recording sheet Google doc. Instead of printing off my own bills, I used money from an old board game (Monopoly Junior). One teacher created her own classroom cash to use for this activity and it was a really nice touch. 
Towards the end of the class, the teacher sold pieces of candy for the money they had collected. I had originally thought about having an auction at the end of the activity or counting totals to declare a class winner. Selling candy was a better idea. It was much faster, so we could spend more time working on problems. It was also more discrete so teams didn't have to declare to the entire class what their group total was. I liked that everyone in the class got to use their cash and they all got something. 
Shut the Box is a traditional game that has a long history. The game is played with two dice and a sheet with the numbers 1 to 9 listed. These numbers are covered as dice are rolled. You might see special dice trays with wooden doors on hinges for the numbers but this equipment is not necessary. There are several variations to this game. I'll explain the rules to the version I play. 
I was recently invited by a grade 6 class to work with them on decimal division. After discussing the learning outcome and reviewing the curriculum guide with the classroom teacher, we chatted about some possible activities. Based on a desired for a hands on activity we decided to try a design activity that we called Spinning Tops. I saw a similar activity posted on Twitter by Jen Carter (@jencarterbc). The activity was originally shared online by Mike Wiernicki (@mikewiernicki) on his blog, Under the Dome. 
We asked students work in small groups (2 or 3) to design a spinning top, using linking cubes. The goal was to construct a top that will spin for as long as possible. Each group designed 3 different tops. They tested out lots of different ideas about what characteristics might lead to a top that spun for a long time. Most groups tried out a variety of shapes and sizes before settling on their three designs. 
Next we gathered some data to test our estimates. A practice round or two is a good idea as students' speed will increase as they figure out a good strategy for chaining the clips together. You might also ask students to do a few trials at each length of chain and take a mean (or perhaps a trimmed mean) to get more accurate data... or you could save this discussion until after students collect some data and then ask them if they feel their data is accurate. 
Hotel Snap from Fawn Nguyen (@fawnpnguyen) In this activity, students design a hotel using multilink cubes. Students are given a number or restrictions on building as well as costs to minimize and profits to maximize. I blogged about this activity, that I called Hotel Cubed. NS Outcomes: Math 9 G01, Math 10 FM01 and Math at Work 10 N01 
The Condo Challenge from Marilyn Burns Students are asked how many cubes are required to build a "Condo" that is 6cubes high. Then they predict how many cubes would be required for a condo 12cubes high. Later they create a mathematical model to predict the number of cubes for a condo of any height. Thanks to Halcyon Foster for suggesting this task! Although she doesn't mention linking cubes, Jo Boaler's Growing Shapes task (from her week of inspirational math) is a similar problem. NS Outcomes: Math 9 PR01, Math 10 RF04 