If your students struggles with math please visit https://www.khanacademy.org/. This is a free website which includes all grade levels of math. Students can look up any topic for 8th grade math and they will have access to videos, practice problems, and guided help on those problems to help your student better understand the concepts.
Online homework also has an online tutor feature (Big Ideas Math homework only). This feature is only available from 3-8 pm PST and only on select homework problems. To use this feature students will click the need help button if they are stuck on a homework problem. If they viewed a video or reviewed the notes and they need help again, the next time they click the need help button there will be an option for a tutor. The online tutor will come up as a chat box and a person will help guide your student so they can solve the problem.