Here, as a downloadable PDF document, is an example of Time Unit Box System (TUBS) Notation Paper for use with your class.
The TUBS notation used in Roots of Rhythm is intended for both non-music and music teachers. It is based on a system designed by Philip Harland in the early 1960s.
A notation in a box means that there is a hit on that count, and an empty box means rest for that count. Numbers, words, or syllables above each box are there to aid in counting the rhythm. When you read the TUBS rhythm through a few times, the sound should become clear, in a way similar to repeating phonetic spellings in a dictionary.