What do the following phrases have in common?

1. SUMMER HOME

2. SUNDAY NIGHT

3. HIGH GRADE

4. TRADE REFORM

5. OLD BUSINESS

6. CHARTER FLIGHT

7. TRAFFIC LAW

8. RELIGIOUS ART

 

Answer:

 

Both words of each phrase name a kind of school:

 

Summer school - Home school, etc.

 

Credit:

Randolph Ross

TWO SCHOOLS OF THOUGHT (#1-6)