Why bother with the Rule of 3 to begin with?: Subject Matter Rigor Timothy Boerst Notice the increasingly varied and detailed use of multiple mathematical representations within one student's math menu problem solving work over the course of the year. 

The top two samples from early in the year are based in numerical and linguistic representations. 

The next two show the incorporation of graphic representations of work (here the use of a table that accompanies numerical components).  
The next pair of work samples shows experimentation with the use of diagrams and algebraic equations later in the year.  
The final two from near the end of the year show a growing integration of graphic, numerical, and linguistic representations used in this student's problem solving work. 