I have two suggestions regarding the Formatting of the practice files.

1. I found the header String to be a bit non-standard.

__ author __ is assigned the author name mostly.
and the date and filename can be generated if needed by __ file __ and os.path.getmtime(__ file __).
If needed then other meta information can be given as __ excercise __.

__author__="John Doe"
__excercise__="Strings" # optional
__date__ ="12/12/1234"  # optional

2. I suggest giving the problem statement as a docstring to a function as it makes it much less ambiguous that where should a particular question's answer should be given.
   Take this for instance-

"""some question"""

def taskx():
    pass

"""some other question"""

def tasky():
    pass

def taskx():
    """some question"""
    pass

def tasky():
    """some other question"""
    pass

The latter looks more neat to me.

Follow the template in test_strings.py for test cases.

Follow guidelines in reverse_string.py

Write tests.

math problems file is named math.py, if someone tries to import math in it, it will import itself.

Instead of resolving the name problem comment is given that assume values instead of importing?

it should be renamed to maths.py

Problem doesn't state what to do when number is negative, neither it says that number will only be positive.
Give proper conditions for input.

Tell explicitly what to return eg.

"""
        Given a number, return string 'even' if it is even or 'odd' if it is odd.
"""

Extra space causing test case to fail.

Improper indents make files look inconsistent.

Many pushes have these naive mistakes which make practice files look weird. Please add guidelines to CONTRIBUTING.md about submitting PEP8 compliant code or better, define standards by giving a template for additions.

I will take care of this and submit a PR.

Follow the guidelines in Folder 'Strings'

Add dicts.py and test_dicts.py with exercises and test cases respectively.

*.pyc should also be added else it will ignore the directory __ pycache __ but not the *.pyc files under it which is making it add __ pycache __ again and again.

Add project ideas following guideline on TEMPLATE.md within Project Ideas folder.

Follow the guidelines from the Folder 'Strings'

Instead of naming them Testers these should be named as
eg. StringsBeginnerTestCase.

Change the print statements to

print("\n.Passed 1. reverse_string with no errors!")