Well, without more context, it's hard to say precisely. It might be a story where the son and his friends have some sort of plan involving the mom. For example, they could be taking her to a surprise party or a family gathering that they've organized. It could also be a more complex story where the mom is in need of assistance and the son and his friends step in to take her to a place where she can get help, like a doctor's appointment or a support center.
There could be several reasons. One possibility is that they are in some kind of trouble themselves and think blackmailing the mom can solve their problems. For example, they might have debts they need to pay off. Another reason could be that they are just bad - natured kids. They might enjoy having power over someone and see blackmail as a way to get that power. Or perhaps they have some secrets that they don't want the son to know and they are using blackmail to keep the mom quiet about those secrets.
Maybe they volunteered at a community garden. The mom showed the kids how to plant seeds, and the son and his friends watered the plants and pulled out weeds.
It could be that the son's friends, perhaps through peer pressure or some kind of mischievous idea, try to get the son to do something that involves his mom in an unexpected way. For example, they might dare the son to invite his mom to a very uncool event for her like a skateboarding competition among kids and then try to make her participate in some way.
The main characters are obviously the mom and the son's friends. The mom could be a kind - hearted and friendly woman. The son's friends could be a diverse group of kids, each with their own personalities, like one might be the joker of the group, another could be really studious.
One time, the son and his friends were planning a sleepover. They were all excited because there was a WWF event happening that weekend. Mom was a bit worried at first but then she got involved. She helped the kids set up a little area in the living room for the sleepover. The boys were talking about their favorite WWF wrestlers all night, and mom even joined in the conversation for a while, sharing some stories about when she was younger and watched WWF too.