We present ALMA 880 \mu m continuum observations of 20 K and M-type stars in the Upper Scorpius OB association that are surrounded by protoplanetary disks .
These data are used to measure the dust content in disks around low mass stars ( 0.1-1.6 M _ { \odot } ) at a stellar age of 5-11 Myr .
Thirteen sources were detected in the 880 \mu m dust continuum at \geq 3 \sigma with inferred dust masses between 0.3 and 52 M _ { \oplus } .
The dust masses tend to be higher around the more massive stars , but the significance is marginal in that the probability of no correlation is p \approx 0.03 .
The evolution in the dust content in disks was assessed by comparing the Upper Sco observations with published continuum measurements of disks around \sim 1-2 Myr stars in the Class II stage in the Taurus molecular cloud .
While the dust masses in the Upper Sco disks are on average lower than in Taurus , any difference in the dust mass distributions is significant at less than 3 \sigma .
For stellar masses between 0.49 M _ { \odot } and 1.6 M _ { \odot } , the mean dust mass in disks is lower in Upper Sco relative to Taurus by \Delta \mathrm { log M _ { dust } } = 0.44 \pm 0.26 .