Gamify it like Super Mario Brothers is a game. Concepts like "fun" and "progress" are good. Nagging, begging, and creating false urgency are bad. Gamification is fine if it doesn't "take over," which it will when business people are running the show.
I feel like there was a time when those coding problem websites with points and leaderboards and such struck a good balance between learning and a game. Then they seemingly all got co-opted by the interview prep industry.