Do your students have trouble identifying the cube root of 64? Or 16 to the 1/4 power?
I use these Radical Benchmarks as a timed test at the beginning of a period once or twice a week during the lessons where we are evaluating rational exponents and eventually solving equations with rational exponents. It reminds students of timed multiplication tests from 5th grade, and they get excited about it! Once they pass benchmark I, I move them on to 2 Benchmark. Passing a benchmark is getting 80% or better.