As long as there's a risk involved and it is some kind of prediction, win or lose type of games, then I would always consider it as a form of gambling.
Sometimes even if it's not directly money as long as it have a value and it is being risk then yes it is gambling.
What do you consider the risk to be about if there is no money at stake? Every single game is a win-or-lose type of game, but not every game in the world is a gambling game or should be considered one unless there is something staked on it and I don't see OP mentioning anywhere that there is some requirement for it.
If there is nothing of value at stake, it cannot be considered gambling at all, and risk is only when you have something at stake which you can potentially lose if you don't make a correct prediction.