https://developer.salesforce.com/trailhead/advanced_formulas/picklist_formulas
Has anyone managed to pass the challenge?
Gives error:
Challenge Not yet complete... here's what's wrong: 
The validation rule does not appear to be working correctly. Marking IsEscalated to true and Priority to Medium did not fire the validation rule.
Testing that same case myself (and some permuations) the Validation rule fires correctly I think...
Here is my validation formula
AND(
ISPICKVAL( Status , "Escalated"),
OR(
IsClosed,
IsClosedOnCreate,
NOT(ISPICKVAL( Priority , "High"))
)
)

The Error I get is: "Step Not yet complete... here's what's wrong: 
Please check that your report includes at least all of these columns: Supply: Supply Name, Unit Cost, Quantity and Total. 
Note: you may run into errors if you've skipped previous steps."
this is my report:

not sure where I made a mistake

https://developer.salesforce.com/trailhead/advanced_formulas/picklist_formulas
Has anyone managed to pass the challenge?
Gives error:
Challenge Not yet complete... here's what's wrong: 
The validation rule does not appear to be working correctly. Marking IsEscalated to true and Priority to Medium did not fire the validation rule.
Testing that same case myself (and some permuations) the Validation rule fires correctly I think...
Here is my validation formula
AND(
ISPICKVAL( Status , "Escalated"),
OR(
IsClosed,
IsClosedOnCreate,
NOT(ISPICKVAL( Priority , "High"))
)
)