Lisa Step!

From MangaHelpers:

This 4-koma style manga follows the adventures of Lisa Hartfield, a foreign English teacher, with her new Japanese colleagues. Lisa has loved Japan since she saw a Japanese DVD at 6-years-old. She studied abroad in Japan during high school, and now she's back as a teacher! She's nervous, but eager to make friends with her new, interesting colleagues. These include Hino Aoi (the friendly gym teacher), Mikogami Koa (the sweets-loving science teacher), Sanjou Chizuru (the calm, motherly art teacher), and Komiya Mito (the conscientious Japanese teacher). Lisa's life as a teacher in Japan has just begun! [tethysdust]