Henderson Riley is known affectionately by Mr. D Math students as Mr. H (or Mr. Chill). Mr. H has been a Florida Certified Math Teacher for over 15 years. Mr. H has now been working with Mr. D Math for the past 5 years. Mr. H is in charge of the math programs for 2 Florida co-ops and teaches over 50% of the live online class sessions offered by Mr. D Math. Mr. H also leads Mr. D Math SAT and ACT test prep courses. Students love his style, humor and ability to communicate math skills in a way that make a lasting difference for them. Mr. H is also a consultant to Sarasota County Schools in Florida offering support for other educators such as classroom management, lesson plan design, test prep for state exams and technology in the classroom.