For each grade 0 classroom, report the total number of students.
SELECT classroom ,  count(*) FROM list WHERE grade  =  "0" GROUP BY classroom
SELECT classroom ,  count(*) FROM list WHERE grade  =  "0" GROUP BY classroom
[{'Classroom': 104, 'count(*)': 4}, {'Classroom': 105, 'count(*)': 5}, {'Classroom': 106, 'count(*)': 7}]