Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_13967239_2 ( senior__4th_year_ VARCHAR, junior__3rd_year_ VARCHAR )

### Question ###
How many classes between senior and junior year for world history

### Accurate SQL ###

SELECT COUNT(senior__4th_year_) FROM table_13967239_2 WHERE junior__3rd_year_ = "World History"