Nanako-San Teki Na Nichijou Dash!!

From MangaHelpers:Nanako is an athletic and free-spirited girl that excels in every sport she does. Many of the sports groups at her school request her assistance at important matches. Where she excels the most is when she finds herself in a bind that will strip her of her clothes, while Keisuke Kawara ogles. You would think Kawara is the luckiest boy alive until you see the end result of Nanako's "accidents." [DrCoke]