Distinguish weather from climate and explain how latitude, elevation, ocean currents, and mountains combine to produce a region's climate.
Weather is what the atmosphere is doing right now or this week -- today's rain, this afternoon's heat wave. Climate is the long-term average pattern of weather in a place, typically measured over at least thirty years. A single snowy week does not disprove a warming climate trend, any more than one hot day proves anything about climate on its own -- the two operate on completely different timescales.
Several factors combine to set a place's climate. Latitude matters most: near the equator, sunlight strikes Earth at a steep angle and stays concentrated, so it is warm year-round; near the poles, sunlight arrives at a low, glancing angle spread over more surface area, so it stays cold. Elevation cools climate too -- temperature drops roughly 6.5 degrees Celsius for every 1,000 meters you climb, which is why tropical mountains can have snow at their summits. Oceans moderate climate: the Gulf Stream carries warm water from the tropics to keep Western Europe far milder than its latitude would otherwise suggest, while cold currents like the Humboldt off Peru's coast cool and dry the air above them. Mountains create a rain shadow -- moist air rises and cools on the windward side, dropping its rain, then descends dry on the leeward side, which is why deserts often sit just past a mountain range.
Mastery looks like: They can state the difference between weather and climate and explain how at least two climate factors combine to produce a specific region's climate.
Common stumbles: Treating a single weather event as proof about climate; forgetting that elevation and ocean currents can override what latitude alone would predict.