This product is perfect for PreK-2. I use it in my first grade classroom and it's well suited for the wide range of students that I have. This is also excellent for ELL students since it's a non-linguistic representation.
This product has 2 Circle Maps for each letter of the alphabet. I do not own Thinking Maps -- I just love them! You can learn more about Thinking Maps by visiting http://thinkingmaps.com.
In my opinion the Circle Map is the easiest for young learners to grasp because they are just defining one thing in context. In this packet, each letter of the alphabet has two circle maps that go with it. They are essentially the same, however, one shows just pictures and the other has the corresponding word written out that matches the picture.
Each letter has nine cards to be cut and sorted. 4-5 of them are examples of words that DO have the beginning sound of the letter written in the middle, smaller circle. These cards should be glued in the large circle. There are a few non-examples for each letter and these cards should just be cut and tossed.
I have used it with the words written out and without depending on the skill level of my students. Sometimes, it is just about identifying the letter and in that case its helpful to have the word written out. In other cases, students are able to simply look at the picture and know if it starts with that particular letter or not. I have a long and short vowel packet for sale here http://www.teacherspayteachers.com/Product/Long-and-Short-Vowel-Circle-Map-Sorts-1183696
One other great way to use this product is to print it on cardstalk, laminate it, and use it has a center. Just keep all the little parts in a bag or envelope! :)