Experiences with "Thermo" curtains / fabric roller blinds as thermal insulation?

I meant the children's rooms. You can try to plan it so that there are 2 exterior walls. I know it usually fails with the 3rd children's room.

You have to plan the shading outside beforehand. No matter what.

Ah now I think I know what you mean: the children's rooms should have windows facing two different cardinal directions. For example, W and N windows or S and W windows?

Our experience is also that external sun protection is miles better than internal. For example, at the south-facing skylight, we initially only had an internal roller blind with a coating. It darkens very well and also blocks quite a bit of heat, but only since I installed an external sun sail from Velux, the heat really stays almost completely outside. Although still not comparable to the other windows with external roller blinds, at least it is something.

Well, that's why I always roll my eyes when someone has a children's room in the north, and then it says "wow, the kids must have the nicer south side." Hello? What's so nice about having to be shaded in the summer? So kids go to the north, then you don’t have to close anything during the day. Our child has the east side, in summer the roller shutter stays slightly open until noon (for whatever reason we don't have a venetian blind there), then it can go all the way up. Since there is mostly school anyway, it doesn't matter. In the living room when we are home, there is an awning + under awning outside, when we are not there, the venetian blinds are down. That worked really well last summer.