My son is almost finished with Math 7 in 6th grade at Swanson and the book he used was Big Ideas Math 7.

It really depends on what level of math your child is in. Start with the summer review packets (one per week): https://www.apsva.us/mathematics/summer-reviews/

In Math 7, a child may be taking:

Math 7 (on level)
Math 8 for seventh graders (advanced)
Algebra (very advanced)
Intensified algebra (extremely advanced)

There's actually an explicit math track. Read here: https://www.apsva.us/mathematics/secondary-math-program/course-pathways/

Textbooks are very old school here in the U.S. these days. My son just started a Catholic MS this year and I was so happy he actually got a math textbook for pre-algebra. In ES, there were no textbooks, Just 1,000,000 copies.

Can anyone tell me what text book APS schools are using for 7th grade math? We'll be moving back to Arlington from an overseas school, and I'd like to do some review with my son as he is coming from a common core school district.