This is a great way to see if your students are applying their strategies as they are reading. You can use this as you introduce each strategy or after all the strategies have been taught.
I use this in my Guided Reading Groups. As students are whisper reading, they write down any "tricky" words they come across (words they have to stop and use a strategy to figure out). They will write down the "tricky"/unknown word by the strategy they used to figure out the word.
First, you will have to model the use of the mats and use a gradual release so students will understand the concept of "why" they are using the strategy mats. You will be amazed how the strategy mats allow the students to monitor their reading and use more than one strategy to figure out words in a text.