Gideon Graif in his book We wept without Tears: Testimonies of the Jewish Sonderkommando from Auschwitz contains collected testimonies from members of the Jewish Sonderkommando, i.e. the people who were forced to work in the gas chambers and crematoria, remove the remains, and so forth, in Auschwitz-Birkenau. It served as the inspiration for the recent Hungarian movie Son of Saul, which attempts to portray the Sonderkommando and their suffering.

Similarly harrowing testimony can be found in Yithzak Arad's book Belzec, Sobibor, Treblinka about the Operation Reinhard Camps in Poland, which also does include if memory serves me right, testimony from Dutch Jews.

The USHMM in its collection of survivor testimony also has a considerable number of testimonies from Dutch Jews deported through the Westerbork Camp to Auschwitz.

In the Netherlands both NIOD, the Institute for War, Holocaust, and Genocide Research as well as the Museum at the Anne Frank House maintain archives and have special aids, collections, and tools for teachers who want to teach their students about the Holocaust.

I hope you'll find what you need there and I'd recommend especially checking out the tools the above mentioned institutions provide for teaching.