SOLO AS91026(1.1) Number

 My learners found it very useful to differentiate between Achievement, Merit, and Excellence.

Criteria
Achievement	uses at least three different numeric methods in an attempt to solve the problem. Ratio and Proportion (need at least one) Rounding and rates (need at least one). Fraction of, Percentage of, Percentage Increase/decrease and GST(need at least one).
Merit	Solve a problem involving one or more of: Selecting and carrying out a logical sequence of steps Connecting different concepts and representations Demonstrating understanding of concepts Forming and using a model Relating findings to a context Communicating thinking using appropriate mathematical statements. What this means? Solve a problem (with working and explanation) using multiple steps
Excellence	Extended abstract thinking. This could involve one or more of: Devising a strategy to investigate or solve a problem Identifying relevant concepts in context Developing a chain of logical reasoning, or proof Forming a generalisation Using correct mathematical statements Communicating mathematical insight. What this means? Solve a problem (with complete working and explanation) using multiple steps and consider rounding issues, multiple solutions, assumptions, comparing different options.

Here is the application on the Practice test Link.