The Challenger book series is an eight-level program which guides adult learners from the beginning stages of reading to pre-GED reading levels. This series helps adult learners improve their reading and reading comprehension through the use of original stories, nonfiction articles, themed units, and phonics charts. Each lesson includes an introduction of new vocabulary words, a short story or article, reading comprehension activities, and various exercises covering the mechanics of the English language. This popular series is utilized by many LEARN tutors who find it a resourceful tutoring and learning material. You can peruse this series by stopping by the El Cajon or Vista Literacy Centers. The Challenger series is also on the LEARN website's materials list: http://www.sdcl.org/learn-materials.html#workbooks.