孩子把紙條對摺成一樣大的幾格，塗出指定的分數；塗好的紙再對摺一次，親手發現 1/2 = 2/4 = 4/8；最後把兩張紙並排，摺到摺痕對齊再比大小。
適合年級：三～四年級（約 8～10 歲）。對應 108 課綱（十二年國教）數學單元：三年級「分數（幾分之幾）」、四年級「等值分數」。各版本教科書的單元順序不同，完整對照請看國小數學課綱對照表。免費、無廣告、不用註冊，手機、平板、電腦打開就能玩，題目有注音，也會念出算式。
陪玩小提醒：再對摺一次，格子數（分母）和塗色的格數（分子）都變成兩倍，但塗色的大小沒有變，這就是等值分數。
Children fold a paper strip into equal parts and shade a fraction, fold a shaded strip again to discover that 1/2 = 2/4 = 4/8, then lay two strips side by side and fold until the creases line up to compare them.
Suits Grades 3–4 (about age 8–10) in Taiwan. Taiwan curriculum (12-year basic education) units: Fractions (Grade 3) and Equivalent fractions (Grade 4). Free with no ads and no sign-up, in Traditional Chinese with zhuyin and in English, with questions read aloud. See the Taiwan elementary maths curriculum map.