That's part of the old code, I haven't gotten around to update it yet...but will be fixed eventually. My current project is to update the second tea conversation with Tamara, then rebuilding the schedules for Vicky/Vanya, Katja and Tamara/Valentina for the house, so they can show up at various places inside the house, kinda like the 5/8 apt and your family. I'll look into the scheduling for after school while doing that.
Edit: The only school days they should not be seen walking to the park is Tues, Thursday and every other Friday, because they both have practice (Cheerleading and Football). but they can be found on those days later in the afternoon in the park...or at Del Parco Cafe randomly, even if its raining.