Since the tables always have the same columns, just list the columns on both:
INSET INTO attendmatsm (col2, col3) SELECT col2, col3 FROM attendmast
Since the tables have the same column, they should all have the same name, regardless of the table name.
If they don't, the chances are the table definition will be wrong, and you will be inserting bad data into your master table.
But this does look like a poor design - I'm not sure exactly what you are trying to do with the data, but the chances are your storage structure is wrong.