This protocol is designed to collect metadata about soil moisture using soil collected for metadata (NOT the sample reserved for metagenomic sequencing) during the sampling protocol. Students will begin by weighing a metal or glass weighboat before and after adding the soil sample (with as much non-soil material removed as possible). The sample will be heated for at least 48 hours to 105 degrees C, and then students will weigh the sample and weighboat again to calculate the drop in the sample’s mass, which represents the moisture. We recommend discussing or practicing how carefully samples should be processed to remove roots and rocks from the sample before weighing. This protocol will generate metadata that should be included with soil microbiome data to describe soil conditions, and adapts a version of the National Ecological Observatory Network’s best practices intended for student use.