In the 80's TV show Misfits of Science, Elvin Lincoln was a scientist that was born with an overactive pituitary gland. He was 6 ft tall when he entered the 7th grade and ultimately grew to 7'4". He went on to study his condition and found a way to temporarily reduce the size of animals using a serum he created. He later created an artificial gland that he put in the back of his own neck. When pressed, the gland secreted the serum into his body, allowing him to shrink down to the size of action figure, somewhere less than a foot tall. This transformation was temporary and lasted for about 15 minutes.
In the show, much was made of the character's awkwardness. He had social challenges and even though he was tall and Black, he was no good at basketball. He was a genius but not very confident in himself. This went along with the theme of the show which had a lot of comedy. Another challenge for El was that even though he could shrink, his clothes couldn't so he would have to bring along clothes from some kind of doll or action figure so he wouldn't be running around as a tiny naked guy. Later, when he would return to his normal size, he had to find his original clothes again. He would usually be called upon to shrink so he could help the team get into or out of places they could do otherwise.
Again this show came out in the 80's so it was great to see a Black character as a scientist back then, even if he was a bit of a bumbler. The character was depicted as kind and non-threatening even though he was a lot taller than everyone else. His power wasn't all that cool but I liked him anyway. The series lasted for only 16 episodes, the last of which was never aired. Still, I remember this show fondly and tried never to miss an episode. Here's the trailer:
