I Used to Know That by Caroline Taggart is an excellent reference and resource for parents. For most of us, by the time our kids have started school a lot of the things we learned have long since been forgotten. This book fills in those gaps.From language arts to math and social studies, this reference covers all of the basic information that the kids are learning or going to learn. It is an excellent primer for parents when their children are starting a new subject or a great refresher for parents to be able to talk intelligently about the subjects their kids are learning. I think the best part is that when it's homework time, I have a great place to turn for more information so that I can immediately help my child.The book covers English, literature, math, science, history, geography and general studies; everything an elementary student is going to encounter. The breadth and depth of information also would make this a great reference for tutors and others helping children with their school work.One great part of me is the math section because I learned many math skills outside the US. When it's time for my son to work on math topics, I have a great reference that talks about the way math is taught in US schools. So, I will not be confusing him with a different method of working through problems.Overall, I love this reference book and recommend it to all parents and caregivers of school-age kids. It is well written and easy to use.