The West London Free School Primary in London has excellent and well-structured pre-recorded lessons for all year groups available on their website. Here is the link for Year 5:
https://www.wlfs-primary.org/Year-5-Len ... /index.aspHe could watch the lessons and do the associated worksheets. Very good quality.
Sorry to hear your son is not getting any live lessons, that is disappointing! I would also recommend purchasing a few CGP or Schofield and Sims workbooks for Maths and English, they only cost a few pounds and are very good.
Good luck!