Drawing after plaster casts is great fun.
It helps a lot to focus on tonal shifts and anatomy.
Nevertheless I find it always astounding to find so much color and reflected light within the shadows and the "white" of the casts.
This cast of a warrior (the so called "fencing Borghese", the original can be seen at the Louvre) at the
cast collection of statues from the ancient world in Berlin was lit from a cool window behind and several warm lights in the front.
The collection is a wonderful place to practice drawing, it's open from thursday to sunday (2 to 5 PM).
The entry is free.
Drawing classes that come with 15 or more students can come outside of the regular opening hours for a fee of 2 €'s per student.