Systems of equations is a great, open-ended math topic to work with.  Over the years, I have developed multiple assessment projects for systems of equations.  I like to give students choice of projects.  Here's a brief introduction to 5 project to use in your own classroom:

• The Ice Cream Parlor:  This project is best for Algebra 1 students or those relatively new to systems of equations.  Students examine the intersection of the price and cost of selling sundaes and ice cream cones.
• It's a story:  This project is the most open-ended of all the projects.  I like to give this to Algebra 2 or PreCalculus students.  Students write a story of related systems of equations problems and solve them using different methods.  Students create a comic book or picture book of the story.  Merging creativity and math is appealing to my brightest of students, but less appealing to the students who prefer specific instructions.  Again, this is why I let students choose.
• Road trip:  This project is tailor-made with students in mind.  Students plan a road trip around the United States.  They select their fellow travelers (friends, relatives, famous people), car type, accommodations and food.  After developing a series of linear equations, they discover what will happen if they take sponsorship.  Can they reduce the price of their trip?
• Simple options:  Another option, particularly when we have less time, is the 5 option project.  I give students a list of 5 systems of equations general problems. Students select one scenario to write problems and solve using different methods.  This is the easiest to implement and assess.
• One day only:  If I have just one day to assess, I could give a test, but I love to use the graffiti activity.  Students create a graffiti wall (on a piece of paper) showing and explaining the major topics of systems of equations.   This activity is the easiest to customize as I can include specific topics or eliminate topics such as matrices if we haven't looked at them such as in Algebra 1.
Need more ideas for systems of equations?  Read more here and here.

This is one of several posts on teaching Algebra 2.  Topics in the series include:
Algebra 2 Day 2
Linear Equations and Functions
Systems of Equations
Logarithms and Exponents
Rational Functions
Probability
Permutations and Combinations

Math Mondays is a bi-weekly blog post (2nd and 4th Monday of each month) sharing tips, ideas, resources, and products for teaching math.  If you have questions or think there is something I should include, you can leave me a message in the comments section below or at the store in the question and answer section.