Trailhead assist is a wonderful tool which can be used to boost your learning through Trailhead of Salesforce.
How to use:
There are 3 buttons, namely
Mark Answers: On click of this button, correct answers would be instantly populated. Users can use this to validate their answers before actually submitting the quiz
Mark and Submit: On click of this button, correct answers would be populated the quiz will be submitted automatically guaranteeing 100% scoring.
Validate Answers: On click of this button, if the user has selected an answer for any question, then it determines whether the chosen answer is correct or not.
And finally, USE IT WELL.
Now includes Winter 20 maintenance solutions