I waited on this one and thought about it for quite some time. I'm a super strict parent 99.9 percent of the time. I knew where my kids were, who they were with, and what they were doing most of the time. Notice I didn't say all of the time, because that is utterly impossible short of stalking them. If they went to someone's house, I had to have met the parents first and knew who was going to be there.......and yes, I called to make certain they were there (not every time, enough to keep them on their toes).
That said.................. No one else has said it so I'm going to put it out there. If a teen decides to do something say drinking, drugs or sex, nothing short of nailing them into a barrel is going to stop them. You can know every single friend they have and their parents and have a good relationship with all of them. Doesn't matter. If they're dead set on doing something, they'll find a way to make it happen.
That is where trust has to come in.
Now I knew my kids friends. Depending on the friend.........they might hang out at my house for a weekend or not hang here at all. Some, like Heather said, still consider me a 2nd Mom, and I had trouble getting them to go home. I never had any issues with any of the kids my kids hung out with regardless of if they were easy child or difficult child. And I know that Nichole's bff was a major drinker/drug user in HS. I knew it when they were basically inseparable. Didn't make any difference. Just because her bff used/drank.........well, let's just say Nichole never touched alcohol until she was over 18.....actually she was nearly 20.......and she's yet to touch drugs. Many of her friends did both or one or the other, including the honor roll students. If I limited their friends due to drinking/drugging neither girl would've had many friends, if any. easy child did manage to go to a few parties in HS where alcohol was served, she thought she was slipping one over on Mom.......but mom knew, and I knew she wouldn't be getting into a car either and there were parents there. But that ended when she took it too far and got alcohol poisoning and the other kids were too scared to go upstairs and tell the parents. She didn't object either, scared the daylights out of her.
I tried to be realistic when it came to my kids during their teen years, not just strict. They were armed with the cold hard facts concerning drugs and alcohol. They also had a free pass to call me if they got drunk/stoned and couldn't get home, or if they didn't want to do either and couldn't get who they went with to bring them home. I knew their friends better than most of the friends parents knew their own kids. I'd have said something to the parents of those I felt had issues......but they were nearly always the "not my kid, they're on the honor roll, foot ball team yadda yadda" and refused to listen. easy child used her free pass once or twice, both times because her ride got zonked, I knew she had drank both times....but she was not drunk so I never said a word. Nichole used hers but because she wanted to leave as a bunch of drug stoned kids were not her cup of tea.
And I'll say right now I kept an eagle eye on Nichole with her now husband. I knew his parents and they seemed like two very responsible adults, no reason for doubt there. They were home when Nichole went over there. And when she was 15 and got preggers with Aubrey?? They had walked in on the kids having sex in his room several times. Did they have a cow? No. Did they put a stop to it? No. Embarrassed they left the room and closed the door and nothing was said. I never heard a word about it until after that pregnancy test came up positive! And heck yeah I came unglued when I found that out........especially after his mom sat there and bawled while I told them Nichole was pregnant. omg
I"m also concerned that your post started out a "I'm feeling left out of the loop" sort of deal to suddenly you don't know her friends well enough to trust them. I'm going to be blunt. You don't need to trust her friends, they're not your child. Jumper will make her own decisions. Jumper is the only one you need to trust and she's given you no reason whatsoever not to trust her. So like Tedo.......I'm worried you've convinced yourself your real worry is over who's she's hanging with. And I'm a bit worried that this sudden change is going to harm your relationship with her.
I understand your worry and you wanting to protect her. That is reasonable and being a good parent. But just dropping in on other parents........... Um, if someone did that to me I'd probably shut the door in their face. No. Correction. I would shut the door in their face. I don't "do" drop ins. Other parents are going to understand your concern, but you are risking alienating them (at best) because if you randomly show up at their house.....it show them with behavior your lack of trust in them as parents. Know what I mean?? It's also rude. And Jumper is at risk of thinking she's done something that makes you not trust her anymore, and it's going to be embarrassing as all get out to have your Mom "drop in" randomly every time you go visit someone. And she may stop socializing outside the home completely.
Kids tend to rebel when they feel smothered and untrusted (because your expectations of them are set lower, so why not?)
Entertain in your home. That's fine. Check to make sure she's where she should be. That's great. Make sure the parents are home. But the rest is quite frankly, over the top.
Sorry if I've made you mad. Not my intention. Just trying to be honest so you can look at it from another point of view.