For years I have used the NC week by week math resources. For grade K-8, they have many resources such as weekly printable games, weekly problems, mental math problems, weekly review sheets, loads of blackline masters and teaching activities to help kids practice math concepts in a fun and realistic way.
The files are separate downloads at the site, so below are compilations of all the various downloads by grade. If you have never seen them, I encourage you to check them out. We use them weekly as review on the last day of each school week.