The distorted-wave method (DWM) is used to study the scattering of electrons and positrons by the rubidium atom for the excitation of the resonance transition. Appropriate static potentials of initial and final states have been used for distorting the incident and scattered projectile electron (and positron) waves, respectively. Differential cross sections (DCS) and electron-photon coincidence parameters lambda and chi are calculated for the first time. The electron impact DCS agree reasonably well with the only available experimental data of Vuskovic et al.