Switch Case in T-SQL

--24.*Countries and Currency (Euro / Not Euro)
SELECT CountryName, CountryCode, Currency =
Case CurrencyCode
      When 'EUR' THEN 'EURO'
      ELSE 'NOT EURO'
END
FROM Countries
 ORDER BY CountryName;

--
SELECT [Name],
[Part of the Day] =
CASE
    WHEN DATEPART(hour, [Start]) BETWEEN 0 AND 11 THEN 'Morning'
    WHEN DATEPART(hour, [Start]) BETWEEN 12 AND 17 THEN 'Afternoon'
    ELSE 'Evening'
END,
Duration =
CASE
    WHEN Duration <= 3 THEN 'Extra Short'
    WHEN Duration <= 6 THEN 'Short'
    WHEN Duration > 6 THEN 'Long'
    ELSE 'Extra Long'
END
FROM Games
ORDER BY [Name], Duration, [Part of the Day];

--9. Age Groups
WITH CTE AS
(
SELECT
(CASE
WHEN Age BETWEEN 0 AND 10 THEN  '[0-10]'
WHEN Age BETWEEN 11 AND 20 THEN '[11-20]'
WHEN Age BETWEEN 21 AND 30 THEN '[21-30]'
WHEN Age BETWEEN 31 AND 40  THEN '[31-40]'
WHEN Age BETWEEN 41 AND 50  THEN '[41-50]'
WHEN Age BETWEEN 51 AND 60  THEN '[51-60]'
ELSE '[61+]'
END) AS AgeGroup, Id
FROM WizzardDeposits
)
SELECT AgeGroup, COUNT(Id) AS WizardCount
FROM CTE
GROUP BY AgeGroup;