Hello! I hope you found something by now. In case not I thought I write what we used for a while. Hauschka Verlag has exercise books for reading, spelling, writing, and mathematics, you can buy on Amazon.de. We have used them with our sons. We also liked the "Lies Mal" books. We have started to use deutsche Fernschule last year. We use it with a teacher. You can just get their materials, too. I like that it comes with the answer keys, and it explains how to explain it to your child (in German of course). My 11 year old was able to use it on his own, and my 3rd grader is just learning to be more independent with it. You can choose between a full elementary program with teacher/ without teacher, just individual subjects (German, Maths, Sachkunde - Science/Social Science/ Healths, Art, ESL) Alternatively, they offer German as a supplement, with optional essay writing. The regular German class is 5x45 minutes/ week in 1st/2nd grade , for 3rd, and 4th grade it is 7x45 min/week. My oldest did 3rd and 4th grade and was done around 35-40 minutes, unless it was writing involved. My third grader needs 45 minutes or more to do his work, plus he needs somebody close by to help. The Deutsch als Ergänzung (as supplement) is shorter. It's calculated to be done in 5x25 minutes/ week. Grade 4-6 can be done online, grade 1-4 are paper based. Our oldest is now starting with ils. https://www.ils.de/auslandsschule/ There is also a German online school. https://deutsche-online-schule.com There is free material online, too. https://www.grundschulkoenig.de/deutsch/ https://www.schlaukopf.de/grundschule/klasse1/ https://anton.app/de/ There are more sites like this online :) Good luck.