《小学自然教学》1997年第5期第24页刊登的《水蒸气凝结实验设计》一文，我们认为这个实验比较直观，便于学生分组观察。但仔细分析这个实验的设计，发现原实验设计只能说明小水珠是由杯里的水蒸气变成的，但不能说明是在什么条件下形成的。原设计见图1。对上述实验中的不足， “Primary School Natural Teaching” 1997 the fifth period published in the page 24 “experimental design of water vapor condensation,” a text, we think this experiment more intuitive, easy for students to observe in groups. However, careful analysis of the design of this experiment, found that the original experimental design only shows that small drops of water vapor from the glass into, but can not explain under what conditions formed. The original design shown in Figure 1. On the lack of experiments,