If the school won’t change then you need to be proactive. There is no reason you can’t request the information when you pick them up. Sure it means taking a few extra steps to go speak to the teacher but they should be able to provide you with that information easy. SO does this with the preschooler. As for the 2nd grader, the school posts a calendar of events online. I understand small schools might not do this. Growing up mine had a board with this sort of information near the front.

You get my point. You have to take it on yourself to get the information since it won’t be handed to you. I know it sucks but you can cry about it or figure it out.

As for step son. Make it through these two weeks then put it on DH. He should be supporting you with the children. During the summer we get the kids for 6 weeks. My partner works nights. I tried my best to help him out but there were times I told him “tough sh*t, it’s your turn.” He’s the one who chose the night job. It’s not my job to pick up all the slack. Make sure DH doesn’t expect you to. It’s not just that it’s his kid it’s that you are a team. Even if the child was both of yours you should still work together.

In our case, some teachers have been really helpful about informing both parents and others just haven't.

Last year, one teacher made sure that DH knew about all school related meetings, including an IEP meeting that BM scheduled and then forgot to go to, so DH was the only parent there. The other teacher wouldn't even reply to DH's emails, even though she always responded to BM - because when BM wanted to look like MOTY, she would copy DH on her emails, so he saw the replies. In most of his emails, he was asking simple questions, but the teacher would not reply. Then DH asked to have a separate conference and that teacher then scheduled BM's conference at the same time. At the end of the year, that SS somehow got an award (not sure how because he's the laziest student ever). BM was notified weeks in advance by SS's teacher (who had met DH several times and knew that BM and DH were divorced). DH got an email from the principal reminding him of the award ceremony, sent at 11pm on the night before the ceremony, so he read it while he was at work, 90 minutes away from the school. He was so angry about that last one, especially when BM sent a group text to her family and DH's family about how proud she was of SS for getting the award. She included DH on that group text, but god forbid she should tell him about the ceremony in advance.

Regarding the ADHD, that's a tough one. Has your SS seen a counselor / behavioral coach? I'm not sure how old he is, but he seems like maybe he could benefit from some behavioral therapy or behavioral incentives to start to manage his own behavior.

I'm sorry, that sucks :(. He should be making sure you get copies of everything. Our school had a parent website it doesn't have all the info but some info... maybe yours does? I make sure BM had access to copies of everything even if I think it's unimportant. She's been told now multiple times to check his backpack and take any and all forms, we keep our copies and only send her hers. She never does. I only try to send them twice then when it's returned crumpled and untouched I toss it.
I've tried different folders. I've tried DH handing them to her physically (which isn't as consistent cuz they don't always see each other) she even put forms he handed to her physically in his backpack and sent them back to us. She asked me if he had school on Columbus day when I got him from her last weekend. She asked me. I made sure she got a school schedule, it's also online. How can she gripe about me being involved in his life and how she's such a great mom and then ask me what days he has off. It's unbelievable. I said no, she said really? Its a holiday. I said i know, he doesnt have it off, and if you paid any attention to his life or the things we both try to get you to participate in you would know!!!! I didn't say that....

I hope this teacher and school find a way to work with you and all future teachers too. When people are really trying to do the right thing it's nice when it works out.

What about you call DS Thursday evenings and ask him what's going on? Or maybe your Ex.... sometimes men do not worry about these things like woman do lol.

But I will march right into his school and kick up some dust, they will send me all the information via email lol...

This is interesting. We kind of had the other side of the story because BM hardly ever made any effort with regard to the school or to school conferences etc BUT she would claim that we didn't keep her informed. School would send her copy of correspondance home to us and she expected DH to drive over and deliver this to her if it happened in the week or on a friday when she didnt have the skids. She would then complain that he hadn't done it that evening that he had received it - for example if he left it a couple of days until the friday evening that they went to hers. Always conflict. So, he told the school that they needed to interact with her directly and send the letters to her - gave her address. He told BM that she was now responsible for her own contact with the school. She was perfectly able to use a telephone, send an email etc. Why should DH have to be her secretary? and so that is how it went, BM was just as sour ofc but who cares? She attended 2 out of 40 school conferences over the years. Always some excuse. It was just all a way of getting at us and her feeling in control.

Now i'm not suggesting you are doing that OP but I am saying that you are entitled and capable of having whatever contact you want with the school, but it seems you are having trouble getting them to comply. Is there a system where you can complain about this? Can you persuade your ex to ask that they inform you too?