A failed sync is the most common reason a student's activity grade looks wrong to them. Two screens tell you what actually happened, and both are worth checking before you reply.
Tracker Sync Errors
System > Tracker Sync Errors lists synchronisation failures and lets you filter by date range and by tracker type. A cluster of failures on one date across many students is a platform problem. A single student failing repeatedly is an account problem, usually a connection that needs to be re-established from their side.
The same information is available as Tracker Sync Errors in the Reports Hub, next to the reports you would look at alongside it.
Data Integrity: manually entered steps
Reports > Reports Hub > Data Integrity (Manual Entries) lists students who typed step counts into their health app by hand.
A sensible order to work through
- Tracker Sync Errors: did the data arrive at all?
- Data Integrity: was the data that arrived actually recorded by the device?
- Data Completeness: is anything else missing, such as an incomplete profile?
- Check Readiness: is the course itself configured so grading can run?
Only after those four is it worth looking at the individual student's account.