Squeak project on weather - draw mts, lake, river & sea; show water evaporation from ocean; wind blows moist air / cloud over to mt; saturated cloud drops rain into lake or mt; cloud dissappears when water vapor volume drops below certain level; have evaporation process run independently - if ocean / lake runs out of water, it stops; couds appear & dissapear depending on how much water they contain; maybe keep a count of raindrops to keep track of water vapor; have viewers to show amount of water in different places; make project in stages, each one building on the previous one, each adding more of the total concepts (evaporation, saturation, cooler clouds can't hold as much water, etc); maybe mtn, river and lake; vary temperature to increase/decrease evaporation;