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The $K2$ Mission has photometrically monitored thousands of stars at highprecision and cadence in a series of $\sim$80-day campaigns focused on sectionsof the ecliptic plane. During its second campaign, $K2$ targeted over 1000young stellar objects (YSOs) in the $\sim$1-3 Myr $\rho$ Ophiuchus and 5-10 MyrUpper Scorpius regions. From this set, we have carefully vetted photometry from{\em WISE} and {\em Spitzer} to identify those YSOs with infrared excessindicative of primordial circumstellar disks. We present here the resultingcomprehensive sample of 288 young disk-bearing stars from B through M spectraltypes and analysis of their associated $K2$ light curves. Using statistics ofperiodicity and symmetry, we categorize each light curves into eight differentvariability classes, notably including "dippers" (fading events), "bursters"(brightening events), stochastic, and quasi-periodic types. Nearly all (96\%)of disk-bearing YSOs are identified as variable at 30-minute cadence with thesub-1\% precision of {\em K2}. Combining our variability classifications with(circum)stellar properties, we find that the bursters, stochastic sources, andthe largest amplitude quasi-periodic stars have larger infrared colors, andhence stronger circumstellar disks. They also tend to have larger H$\alpha$equivalent widths, indicative of higher accretion rates. The dippers, on theother hand, cluster toward moderate infrared colors and low H$\alpha$. Usingresolved disk observations, we further find that the latter favor highinclinations, apart from a few notable exceptions with close to face-on disks.These observations support the idea that YSO time domain properties aredependent on several factors including accretion rate and view angle.

The many-faceted light curves of young disk-bearing stars in Upper Sco and $\rho$ Oph observed by $K2$ Campaign 2