A nature museum asked Sara's class to fix a wildlife（野生动物）/ˈwaɪlˌdlaɪf/ wall. They had to work in groups（分组合作）/wərk ɪn grups/ and learn how animals lived in the wild（在野外）/ɪn ðə waɪld/. Its cards showed an ant（蚂蚁）/ænt/, bee（蜜蜂）/bi/, butterfly（蝴蝶）/ˈbətərˌflaɪ/, bird（鸟）/bərd/, eagle（鹰）/ˈigəl/, fox（狐狸）/fɑks/, wolf（狼）/wʊlf/, rabbit（兔子）/ˈræbɪt/, mouse（老鼠）/maʊs/, snake（蛇）/sneɪk/, lion（狮子）/laɪən/, tiger（老虎）/ˈtaɪgər/, elephant（大象）/ˈɛləfənt/, giraffe（长颈鹿）/ʤəræf/, monkey（猴子）/ˈməŋki/, panda（熊猫）/ˈpændə/, penguin（企鹅）/ˈpɛŋgwən/, shark（鲨鱼）/ʃɑrk/, and whale（鲸）/weɪl/. Such（这样的）/səʧ/ a task mattered because several animals were somewhere（某处）/ˈsəmˌwɛr/ they could never live.

The group worked within（在……之内）/wɪˈθɪn/ four habitat（栖息地）/ˈhæbəˌtæt/ areas: forest, grassland（草原）/ˈgræsˌlænd/, desert（沙漠）/ˈdɛzərt/, and sea or ice（冰）/aɪs/. For example（例如）/fər ɪgˈzæmpəl/, a little（小的）/ˈlɪtəl/ penguin stood（站立）/stʊd/ in the hot desert, while a huge（巨大的）/juʤ/ elephant sat on floating（漂浮的）/ˈfloʊtɪŋ/ ice. A shark appeared in a tree, and a sheep（绵羊）/ʃip/ was labelled（标记为）/ˈleɪbəld/ as an insect（昆虫）/ˈɪnˌsɛkt/. “Whatever（无论什么）/ˌwəˈtɛvər/ looks silly（愚蠢的）/ˈsɪli/ still needs a reason before we move it,” Sara said. “Find out（查明；弄清）/faɪnd aʊt/ what the evidence（证据）/ˈɛvədəns/ says.”

They checked body features（特征）/ˈfiʧərz/ first. A bee, butterfly, bird, and eagle each had a wing（翅膀）/wɪŋ/ and could fly（飞）/flaɪ/. A snake had none（一个也没有）/nən/. The whale itself（它自己）/ˌɪtˈsɛlf/ lived in water, although it was not a fish. Penguins could not fly, but their bodies stayed warm where water could freeze（结冰；冻住）/friz/. Whenever（每当）/wɛˈnɛvər/ the class found a wrong card, they wrote（写下）/roʊt/ the fact themselves（他们自己）/ðɛmˈsɛlvz/ before moving it.

Next they studied food. A lion, tiger, wolf, fox, shark, and eagle could hunt（捕猎）/hənt/. The rabbit, mouse, sheep, elephant, giraffe, monkey, and panda needed different food. One label（标签）/ˈleɪbəl/ called the lazy（懒惰的）/ˈleɪzi/ panda ugly（难看的）/ˈəgli/ and the tiger handsome（英俊的；漂亮的）/ˈhænsəm/. Sara removed（删除）/riˈmuvd/ both opinions. Pretty（漂亮的）/ˈprɪti/ or ugly was not useful（有用的）/ˈjusfəl/ evidence about a habitat.

A lantern（灯笼）/ˈlæntərn/ above the wall lit（照亮）/lɪt/ a rainbow（彩虹）/ˈreɪnˌboʊ/ after the final card moved. The display（展览；展示）/dɪˈspleɪ/ was now really（确实）/ˈrɪli/ clear: desert animals had to stay away from（远离）/steɪ əˈweɪ frəm/ ice, sea animals stayed in water, and insects were not mixed with sheep. The class had not written（写成的）/ˈrɪtən/ everything about every animal. As a result（因此）/ɛz ə rɪˈzəlt/, visitors（访客）/ˈvɪzɪtərz/ could learn the important differences without reading a catalogue（目录）/ˈkætəˌlɔg/.