I would recommend getting your little readers subscribed to a website that is sponsored by Sylvan Learning. It is a great site for all students, whether they are in public, private, or even home-schooled settings. It is a very comprehensive AR list with tests and prizes. The thing that really impressed me about this site was that I subscribed as my child. As soon as I gave all of the information linked to my email address, I received a verification notice to alert me to the fact that my child had just subscribed to this website. It is safe and something that you as the parent can monitor to keep up with your child's progress. It even rewards your child with prizes for accumulation of points. Best of all, it is FREE!!!
Check it out! Your kids will be excited about what they will find. Teachers, you will find that there is alot that you can benefit from here as well.