There are other sites that are excellent supplemental math resources that can be used in conjunction with a full math curriculum.
Some are free; some are subscription which you would need to pay for on your own.
Freckle Math – free online site which differentiates skills/topics for student
Beast Academy – monthly subscription available
ABC Mouse – an online subscription site with engaging graphics and learning paths.
IXL - subscription site for directed learning on specific math skills
Spectrum Math Workbooks.
Ed Reports.org reviews curriculums and scores each on rigor, usability, and focus and coherence. It is a great site to look at curriculum you are considering for use math and language arts.