Errol Miller received his primary education at Central Branch and Half-Way-Tree All Age Schools. Central Branch All-Age was then located on Church Street and Half-Way-Tree All Age was located at 4 Hope Road. He represented Half-Way-Tree All Age School cricket as a wicket-keeper and batsman. He also represented the school in the All-Island Elocution Contest and won first place in the under “twelve-years-old” category. Miller sat the entrance examinations of Jamaica College and Calabar High School and was accepted by both. His parents chose Calabar.
Errol Miller received his secondary education at Calabar High School. He was successful in both the Cambridge University School Certificate and Cambridge University Higher School Certificate Examinations. While at Calabar he represented the school at athletics, cricket, and football. In athletics, he held the records in the hurdles in Class 3 and Class 2, was on the track team at the Boys Athletic Championship for five years, including being a Class 2 member of the team that won the Boys Athletics Championships in 1955 and in Class 1 was a member of the winning Medley Relay Team. He also played on the School’s Sunlight Cricket Team for five years and was the Captain in the last year. He was selected and played on the All Schools Team for two years and in the second year was invited for Trials for the selection to the Jamaica Cricket Team. He made it to the Final Trials, with 22 players but was not selected to the Jamaica Team. At Calabar, Miller was a fast bowler. He also played in Senior Cup Cricket League for Lucas Cricket Club, while still at Calabar. In Sixth Form he was a Prefect and House Captain of Athens. During his stay at Calabar, he was awarded several prizes at the Annual Prize Giving. On several occasions, he received the prize for being the best all-around student based on performance in academics, sports, and participation in school activities.
Upon graduating from Calabar High School, Miller was admitted to the University College of the West Indies (UCWI) in 1958. He was one of the recipients of fifty Scholarships offered by the Government of Jamaica tenable at UCWI that year. At that time the University College was affiliated to London University in England. He was admitted to the Faculty of Natural Sciences. At the end of his first year at UCWI, Miller won the B Sc. Part 1 Prize awarded to the top performing student in the Faculty of Natural Science, having obtained distinctions in Botany, Chemistry, and Zoology. He graduated from in 1961 with a B Sc. degree in Botany and Zoology. He represented the University College at cricket, football, and athletics and was awarded colours for cricket. He was also Vice President of the InterVarsity Christian Fellowship (IVCF).
At the post-graduate level Miller read and was awarded:
- The Diploma in Education of the University of the West Indies in 1964 with Distinctions in Theory and Practice.
- The Higher Diploma in Education of the University of the West Indies in 1965.
- A Masters of Arts in Education, with distinction, from the University of the West Indies in 1966.
- The Ph. D in Education of the University of the West Indies in January 1970, having submitted his Thesis in the summer of 1969. Miller was the first recipient of both the Masters and the Ph. D in Education awarded by the University of the West Indies. For both degrees, Miller specialised in the Social Psychology of Education.
- A Post-doctoral Fellowship in Science Education at the Harvard Graduate School of Education for the academic year 1969 – 1970.