Student ID at 16? Is an Oyster ZIP card enough?

[dornkorus]

DS is 16 and just finishing year 11 and will be going into sixth form in September. I know that various entertainment/retail outlets offer student discounts with "Student ID" but don't generally define what ID is acceptable. We live in London, so DS has an 11-15 Zip card that will soon be replaced with a 16-18 Zip card. Are they usually acceptable as Student ID?

When we google for other types of student id there are various types that come up, but all seem very commercial, aimed at collecting their data, which is offputting.

Any tips appreciated!

College or 6th form access card for student ID.
Provisional driving licence for age ID.

If they have a school/college email address it's worth signing up for something like the Unidays or Studentbeans websites where they can get good discounts on many high street shops and restaurants etc.