These are the number cards 1-100 that I use with my students for many of my math mats. They are color coded by each group of tens. For example: the twenties, the thirties..etc. I have made six sets to use at my guided math table. I separate numbers 1-20 so that I can adjust the difficulty of each skill and differentiate instruction easily. I use velcro on the back to make them easier to work with.