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Teach knowledge, notmental skills

Teach knowledge, notmental skills
Teach knowledge, notmental skills

T each knowledge, Not “Mental Skills’

E.D.Hirsch

E.D.(Eric Donald) Hirsch is a professor of English at the university of Virginia. Among his main books are the aims of interpretation and cultural literacy: what every American needs to know(1987). Hirsch gained recognition with cultural literacy: What Every American Needs to know , in which he indentified 5000 names, dates, facts, and concepts that he claimed every educated person should know in order to function effectively in society. “teach knowledge, not … mental skills?” originally appeared in the New Y ork times newspaper on the opinion page.

1The children at Public school 67 in the South Bronx are all African-American or Hispanic, and all are poor enough to qualify for free lunch. In the late ’80s, the school was so ineffective that the district board was about to shut it down.

2But in 1991 a new principal, Jeff Litt, introduced a grade-by-grade “core knowledge”curriculum. The student s’academic performance has risen so dramatically –their reading scores, for instance, were up 13.5 percent last year –that Mr. Litt has had to limit the flow of curious visitors to his school.

3The curriculum was developed by the core knowledge foundation, a nonprofit group I founded that advises public schools free of charge. Mr.

Litt became an enthusiast of the grade-by-grade sequence after visiting the three Oaks school in lee country, fla., the country’s first core-knowledge school. This year the Bronx will get two more core-knowledge schools, joining about 100 others across the nation.

4What’s the secret of their success? About 50 percent of classroom time is spent teaching each student a core of knowledge that is the same material offered to every other child in the same grade throughout the school.

5To understand why this plan has contributed to strong academic improvement, consider how rare such common sense is.

6Typically, school guidelines are couched in terms of learning skills, rather than the content of learning. For example, school guidelines might

contrast, the core knowledge guidelines specify that first graders will “identify the seven continents”and “learn the difference between

another. A Connecticut mother wrote me that her young twins, who were in separate classrooms at the same school, were learning totally different things.

8Because there’s no consistency in what children were taught in

previous grades, teachers have to make a disastrous compromise: either they fill in knowledge gaps for all students in the class, making progress excruciatingly slow, or they go forward at a pace suited to the more prepared students, leaving others behind.

9Such a hit-or-miss approach does the most harm to disadvantaged students who usually depend on school alone for access to academic knowledge. But even advantaged students are hurt by being left with huge knowledge gaps or by being bored with repetition.

10That problem is avoided in the best and fairest school systems in Europe and Asia, which offer programs similar to the core-knowledge schools. Since students have learned the same things, teachers can build on that shared foundation and bring the whole class forward.

11It is a promising sign that the Clinton Administration’s new education bill employs the resonant new phrase “content standards.”Nonetheless, most educational reformers continue to emphasize skills and scornfully dismiss the teaching of “mere facts,”which they claim are destined for quick obsolescence.

12Hearing few contrary voices, well-intentioned philanthropists and politicians echo such slogans as “learning-to –learn skills, “critical-thinking skills” and “problem-solving skills.”

13Y es, problem-solving skills are necessary. But they depend on a wealth of relevant knowledge. Meanwhile, street-smart children in the

Bronx and elsewhere demonstrate outside school that they already possess higher-order thinking skills. As Jeff Litt has shown, what these students lack is not critical thinking but academic knowledge.

14Contrary to proponents’claims, emphasizing all-purpose mental skills to “prepare children to the 21st century”is not new. The tired slogans have dominated U.S. educational discourse for over 40 years, and are a chief cause of the curricular chaos.

15Leaving such slogans behind, and following the lead of effective systems in Europe and Asia, P.S. 67 demonstrates how we can achieve excellence and fairness for all.

In conclusion 总之

Adage:n.格言,[语]谚语;箴言saying, saw, proverb, motto

浙江大学远程教育学院2012年秋冬第7次作业english

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的度数;

三角形强化训练和深化 ? 1、如图a 是长方形纸带,∠DEF=25°,将纸带沿EF 折叠成图b ,再沿BF 折叠成图c ,则图c 中的∠CFE 的度数是_________°. 解析: 由题意可知折叠前,由BC//AD 得: ∠BFE=∠DEF=25°将纸带沿EF 折叠成图b 后, ∠GEF=∠DEF=25° 所以图b 中,∠DGF=∠GEF+∠BFE=25°+25°=50° 又在四边形CDGF 中,∠C=∠D=90° 则由:∠DGF+∠GFC=180° 所以:∠GFC=180°-50°=130° 将纸带再沿BF 第二次折叠成图C 后 ∠GFC 角度值保持不变 且此时:∠GFC =∠EFG+∠CFE 所以:∠CFE=∠GFC-∠EFG=130°-25°=105 2、在Rt △ABC 中,∠A =90°,CE 是角平分线,和高AD 相交于F ,作FG ∥BC 交AB 于G ,求证:AE =BG . 解法1: 【解析】证明:∵∠BAC=900 AD ⊥BC ∴∠1= ∠B ∵CE 是角平分线 ∴∠2=∠3 ∵∠5=∠1+∠2 ∠4=∠3+∠B ∴∠4=∠5 ∴AE =AF

过F作FM⊥AC并延长MF交BC于N ∴MN//AB ∵FG//BD ∴四边形GBDF为平行四边形 ∴GB=FN ∵AD⊥BC,CE为角平分线 ∴FD=FM 在Rt△AMF和RtNDF中 ∴△AMF≌△NDF ∴AF=FN ∴AE=BG 解法2: 解:作EH⊥BC于H,如图, ∵E是角平分线上的点,EH⊥BC,EA⊥CA, ∴EA=EH, ∵AD为△ABC的高,EC平分∠ACD, ∴∠ADC=90°,∠ACE=∠ECB, ∴∠B=∠DAC, ∵∠AEC=∠B+∠ECB, ∴∠AEC=∠DAC+∠ECA=∠AFE, ∴AE=AF, ∴EG=AF, ∵FG∥BC, ∴∠AGF=∠B, ∵在△AFG和△EHB中, ∠GAF=∠BEH ∠AGF=∠B AF=EH ,∴△AFG≌△EHB(AAS) ∴AG=EB, 即AE+EG=BG+GE, ∴AE=BG. 3、如图,等腰直角三角形ABC中,∠ACB=90°,AD为腰CB上的中线,CE⊥AD交AB 于E.求证∠CDA=∠EDB.

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