(Stats Challenge) Code Check: Room for Improvement?

# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}

# Recommended  by PEP-8 styling
# Use 4-space indentation instead of 2 spaces
# Use underscore instead of camelCase for variable names. For example:
#     num_classes instead of numClasses
#     most_classes instead of mostClasses

def most_classes(dict_teachers):
    trophyTeacher = ""
    mostClasses = 0
    # numClasses = 0 #<-- initialization not needed since it is set in each loop pass

    # alternative for loop structure using enurmerate
    # for teacher, class_list in enumerate(dict_teachers):
    for teacher in dict_teachers:
        # num_classes = len(class_list)
        numClasses = len(dict_teachers[teacher])
        if numClasses > mostClasses:
            mostClasses = numClasses
            trophyTeacher = teacher
    return trophyTeacher

def num_teachers(dict_teachers):
    # This entire function can be simplified to
    # return len(dict_teachers)
    amountTeachers = 0
    for teacher in dict_teachers:
        amountTeachers += 1
    return amountTeachers

def stats(dict_teachers):
    # new_list = [] #<-- initialization not needed
    second_list = []
    # numClasses = 0 #<-- initialization not needed

    # enumerate could also be used here
    for teacher in dict_teachers:
        numClasses = len(dict_teachers[teacher])
        # Since the split string is not present in 'teacher', no split will happen
        #   new_list = teacher.split('<string to list>')
        # instead simply start the new_list with 'teacher'
        new_list = [teacher]
        new_list.append(numClasses)
        second_list.append(new_list)
    return second_list

def courses(dict_teachers):
    new_list = []
    for courses in dict_teachers.values():
        # instead of looping through each course in courses, used the 'extend()' method
        #   for course in courses:
        #       new_list.append(course)
        new_list.extend(courses)
    return new_list