Relevant anecdote: For a high school ICT project my class had to make an educational game in Visual Basic. I made a 'math invaders' clone where you answer simple algebra sums (e.g. 5 + x = 12) to defeat the relentless hordes of aliens. At home my 8yo brother watched me play for about 5 minutes, then exclaimed 'Oh I get it, the letters are like numbers that you have to find!', then went on to play the game himself for hours. He learnt algebra about 6 years before any of his classmates through gamification, and years down the track enjoys math more than many of his friends.