If they haven't, the outcome could be that they'll turn away totally from attempting to achieve, turn from the family (then or later), head off in a totally different and sometimes socially unacceptable direction, become deeply anxious, stressed or depressed, or take their own life.
We all want our children to do well but we also have to take care in how we approach supporting them. Every youngster, including siblings, is different and each develops at their own pace. We need to recognise this.
We also need to recognise when we might be trying to live our lives through our children, trying to get them to achieve where we failed. Making the stakes too high can be counter-productive.
When they're already feeling pressured by the school workload, going on and on at them isn't helpful. Repeating the same old things that haven't encouraged them in the past won't suddenly start working. Nor will getting extremely angry or punishing them it might work short-term but will fail long-term. It just shows that we've lost perspective.
We know how our own stress can make us sleepless, short-tempered and over-anxious. We can easily move from productive to survival mode. One survival technique is avoidance. Or not caring. Children use this a lot. It doesn't necessarily mean they're being lazy.
At 15 and older, a more a collaborative approach is likely to work better. Sometimes there's little we can do to help, but we can express our understanding of the pressure. We can sit down with them and get them to talk through what's going on - there's still truth in the saying that a problem shared is a problem halved and we might be able to make a useful, relevant suggestion or do something to lighten their load in other areas. We just need to make sure we listen and don't talk too much.
And we can still discuss consequences and set agreed, temporary limits on, for example, social or extra-curricular activities. In return, we could temporarily pick up some of their chores or even become an administrative assistant. Note, I wrote ''assistant'' not ''boss''.
If specific help is need, it's better outsourced to a tutor, leaving us free to provide emotional and other support.
Our youngsters don't usually want to let us down, but sometimes they can't see their way out of something that, at that moment, seems overwhelming. And our own anxiety can make us oblivious to what's happening to them. We need to make sure we aren't letting them down.
