Answer:   Before answering your question, allow me to ask another: "Is it necessary to be competitive to succeed in the material world?" Competition always places individuals against each other; competitors must fight one another. And on the battlefield of competition, one competitor must lose for the other to win. Competition makes us treat others as enemies, as threats or obstacles that stand in the way of what we want to achieve.

But those whom we call competitors are actually fellow travelers on the journey of life, like us, trying to do the best they can. If we look upon them as friends instead of enemies, we can develop a spirit of cooperation and assist each other in reaching our respective goals. A spirit of cooperation can help us succeed in life, perhaps even better than the attitude of competition.

To succeed in any endeavor, the two most important factors are proper guidance and sufficient effort. When children are given proper guidance, and when they strive hard for their goals, they will certainly succeed.

Let us rephrase your original question: "Is it better to raise our children to succeed in the material world or to be content with whatever they have?" The answer to this question is: both. Dharma demands that we fulfil our duties to ourselves and others. Generally, that requires us to strive hard to be successful in worldly affairs. But if we are always unhappy with what we have not achieved, we will be miserable and we will make others miserable as well. So, we can strive hard to achieve as much as possible, while maintaining a prayerful attitude to gracefully accept what we cannot achieve.