Gas accretion onto galaxies is believed to drive the average star formation rate. However, there are few observations of this accretion for late-type galaxies, especially impacting the disk or triggering a starburst in the disk. Here we propose optical and Halpha imaging of four metal-poor tadpole galaxies that have local metallicity drops by a factor of 5 in relatively large off-center starburst clumps. The bursts and the unusual metallicities suggest recent accretion of large gas masses. Photometry plus SED modeling will determine the ages, masses, and luminosity distributions of the star clusters and star complexes in the bursts. Halpha will reveal ionization rates along with feedback and possible accretion structures. The sample represents the nearest low-mass galaxies that have high-resolution metallicity variations and single dominant starburst clumps. The results have broad implications for understanding the mass-metallicity relation for galaxies, the formation and feedback of stars and massive clusters in accretion-induced starbursts, and the origin of metal-poor globular clusters in the early universe. Only HST has the combination of angular resolution and sensitivity to carry out this program.