I was in trouble. Students hated my class teaching at a Middle School and I thought about leaving my career. One day, I decided to teach them as simply as possible, so I used paper and pen and created simple rules. IT WORKED!!!! Of 168 students, they averaged 48% improvement over 4 weeks, pretest to post test. (So, a student might have 30% pretest and improved to 78%.) Three students went from 0% pretest to 100% post test. I knew once that class ended that I could turn it into a product. It's very good with Verbal Learners, those wanting a simpler algebra, and those who don't like calculators. I've been a teacher for 15 years, both public and private schools.