Last week, one of my older teens was sitting in the kitchen replying to her emails while I prepped dinner. “Help me write a really good excuse,” she asked. A teacher had asked her to speak at a school function that she didn’t want to be involved in.

“Just write, ‘I’m honored to be asked, but I can’t help you this time,'” I suggested. This turned out not to be so helpful.

“MOM. Please. That will not work. I need to say why I can’t do it.” I walked around the island to look at her email. She had typed not one but two paragraphs detailing why should couldn’t go. Nothing she had written was exactly true.

Even though she wasn’t interested in attending, she hadn’t really said no; it was as though she was trying to paint a picture of a life so disastrously busy that her teacher would have no choice but to retract his invitation.

[Read: 5 Ways to Help Your Teen Develop a Sense of Purpose.]

It can be really hard to say no. Teenagers, especially, want to be liked. They don’t want to disappoint us or their friends or their teachers. But they often don’t know how to say no, and so they find themselves hemming and hawing — and often saying yes instead.

The ability to say no is a critical life skill, and one that our kids probably won’t learn without explicit instruction and practice. We adults tend to emphasize that kids should “just say no” to the big things — sex and drugs and anything that might kill them. But if they can’t confidently decline an invitation or choose not to do someone a favor, how will they say no when it matters more?

Here are some ideas for teaching kids to say no that have worked for me:

1. Teach them to be clear about their priorities and truthful in their refusal.

Saying no is easier when we’re clear about our priorities; it’s even harder to decline a request when our reasons for doing so seem unimportant. My daughter has a lot going on this semester that’s more important than her teacher’s event. She needs to be careful about what she commits to on school nights. Saying, “I’m not that interested” seemed selfish to her. But it was also true for her to say, “I’m sorry to disappoint you, but I’m already committed to something else that evening.” What was she committed to? It didn’t need to be anything more than completing her homework and getting to bed at a decent hour.

Even though this response was vague, it was the truth. Untrue excuses and white lies lead to further entanglements and greater stress.

Telling the truth is not the same as sharing more details than are necessary, even if someone asks why you can’t help them out or come to their party. Detailed explanations imply that the other person can’t handle a simple no — or that the kids need help working out their conflicts.

[See: 10 Concerns Parents Have About Their Kids’ Health.]

2. Rehearse a handful of simple and vague go-to ways to say no.

When teens make a specific plan before they are confronted with a request, they’re far more likely later to act in a way that’s consistent with their original intentions.

Something simple — like saying, “That doesn’t work for me this time” — is almost always sufficient. But kids will need to come up with something they would feel comfortable saying. Help them pick a default way to say no, and then help them practice saying it before they need it. Here are some ideas:

— “Thank you so much for thinking of me! I’m sorry I’m not able to help you at this time.”

— “I can’t be there, but I will tell my friends about it and post it on social media.”

— “I wish I could, but it’s not going to work out for me this time.”

3. Help kids think about the future rather than the present.

Research shows we often choose what is most satisfying in the present rather than what will make us happiest in the future — and pleasing others by saying yes can be far more pleasant in the present than saying no.

We can help kids make better decisions by encouraging them to picture themselves moments before the event in question (or in the aftermath of, say, not having enough time for homework or sleep). Would they be relieved if it were canceled? If so, encourage them to say no now so they don’t find themselves trying to weasel out of it later.

4. Encourage persistence.

If their “no” isn’t accepted with grace, help them practice repeating their refusal calmly, using the same words. This will help the other person see that they are sticking to their “no,” and that their pestering isn’t changing their answer. If that doesn’t work and they need something else to say, encourage them to express empathy. For example, they could say, “I understand that you are in a tough spot here,” or, “I know this is hard for you to accept.”

If the other person still won’t back down, teens can share how they are feeling. For example: “I feel uncomfortable and a little angry when you continue to ask me even though I’ve declined.” Have them focus on their emotions — how the other person’s refusal to accept their honest decline is making them feel — and not the logistical details or logic for their refusal. (This takes a good deal of courage, to be sure. Even thinking about this is a step in the right direction.)

5. Say no for them.

My kids have permission to use my husband and I as an excuse when they are having a hard time saying no. We can always easily tell when they’re asking for permission to do something they don’t want to do. When this happens, we’ll often clarify how they feel. (“Do you think it’s a good idea to go to that concert?” Or, “How badly do you want to help out with that?”) Then when the response comes back lukewarm, we’ll put the hammer down. Very occasionally, the kids will indicate to us that they need us to say no firmly and within earshot of their friends or in a text that they can show their friends. We’re happy to provide this service; they don’t always have to do the hard work of saying no on their own.

[See: 10 Ways to Broach the Subject of Sex With Your Teen.]

Finally, if kids are still feeling nervous about saying no, have them take a moment to call to mind the respect they have for themselves and how they’d like others to respect them as well. It takes courage to consider your own needs and priorities along with the needs of others. But it’s worth it. In the long run, the ability to say no is a little-known key to our kids’ happiness.

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Teaching Teens to ‘Just Say No’ originally appeared on usnews.com