Minimally different surds by @shivmckena55 is a task which helps students to spot the underlying pattern of root 2 and root 3 in these common surds which we are required to evaluate.  Possible extension is to ask learners to generate the sequence of surds which simplify to multiples of root 5 or root 7 etc.  Another question might be where root 6 comes into all of this since its a multiple of both root 2 and root 3.  We might ask students to order the surds on a number line.  Vast scope beyond simply doing the evaluations.