Search	Terms	Hits
1	class size*	0
2	“Class Size” OR “Classroom Environment” OR DE “Crowding” OR “Flexible Scheduling” OR “Small Classes” OR “Teacher Student Ratio”	3
3	(Primary School*) or (Elementary school*) or (secondary school*) or (middle school*) or (Junior high) or (“Middle Schools”) OR (“Elementary Schools”) OR (“Secondary Schools”) OR (“Junior High Schools”)	29
4	learn* or develop* or perform* or achiev* or abilit* or outcome*	39712
5	learn* or develop* or perform* or achiev* or abilit* or outcome* or improve*	41059
6	Intellectual Development*	7
7	“Class Size” OR “Classroom Environment” OR DE “Crowding” OR “Flexible Scheduling” OR “Small Classes” OR “Teacher Student Ratio” AND (Primary School*) or (Elementary school*) or (secondary school*) or (middle school*) or (Junior high) or (“Middle Schools”) OR (“Elementary Schools”) OR (“Secondary Schools”) OR (“Junior High Schools”)	3
8	“Class Size” OR “Classroom Environment” OR DE “Crowding” OR “Flexible Scheduling” OR “Small Classes” OR “Teacher Student Ratio” AND Learn* or develop* or perform* or achiev* or abilit* or outcome* or improve* or Intellectual Development* AND Primary School* or Elementary school* or secondary school* or middle school* or Junior high or “Middle Schools” OR “Elementary Schools” OR “Secondary Schools” OR “Junior High Schools”	3