DAY HOC BUdi 2 THEO HlTdNG TRAI NGHIEM, KHAM PHA Biii "LUYEN TAP VE PHEP CHIA CHO SQ CO 2 CHIT SO" [TOAN 4]
P H A N DUY N G H l A *
H
ien nay, mpt trong nhung giai phap tich cue nham khich le, 161 cuon hgc sinh (HS) hoc tap la giao vien (GV) can tliiet kebai day theo hudng trai nghiem, khim phi. Bai viet de cap mgt each tiep can ve day hgc buoi 2 bai: Luyen tip ve phep chia cho sdc62chus6'(f oan 4) theo hudng to chuc cho HS trai nghiem, kham pha.1. Khdi dong, ciing co'klen thuc da hoc Thong qua tro choi hgc tap, sau khi cung co kien thu'c da hgc cho HS, GV co the to chuc eho HS choi tro choi sau:
Gl'.-To ehu'c tro choi mang ten "Di'u tn/dng 24"
(kJp CO 25 em) cho cac HS trong ldp cung tham gia, - Cau hoi de chgn ngirdj choi chinh: Khithue hien phep chia hai so CO tan cung la cac chdsoO.de thuan tien ta lam the nao? (Mgt em tra Idi diJng vi nhanh nhi'tdugc chgn lam ngudi chai ehinh).
• Ngudi chgj chinh len ngoi a ban G V va cung thi dau vdi 24 ban con lal.
GI/.-Dat tinh roi tinh: 2 8 8 : 2 4 .
- 25 em cung lam vao bang con, khi ngudi chdi chinh iam xong va gio bang len, 24 ban con lal phai dung lai vagicf bang len. Ban nao lam cham hoaelam sai thi khong dugc tinh diem (mdi phep tinh dung dugc 2 diem).
GV: Em hay cho biet bai lam cua minh da sai d dau {vdinhOngem lam saip em hay sua lai cho dung.
HS tiep tuc thuc hien vdi4 phep tinh kiiac (18000:
750; 1855 :35; 9146 :72; 12345 : 67),
^ Ket thuc tro chdi, cong diem lai, nhimg HS dat 10 diem sedUdc khen vacac ban thudng mgt trang phao tay, GV can co su dgng vien doi vdi nhung em dat (Hem thap (trong quatrinh chai, neu ngudi chai chinh Hm sai^i thay ban khic, chgn mgt trong cac ban iim dung va nhanh nhat dcac phep tinh da lam).
GV CO the linh hoat chpn va thay doi tro choi nh§m tao hdng thu, phat huy tinh tich cue cua HS,
2. Trai nghiem, kham pha
GV:Cac em da dat va thuc hien diing phep tinh:
12345:67= 184 (du17).Vay,dephep chia do khong condu.taiam thenao?
WS;Thao luan theo nhom doi (5 phut), Nhom //Dephep chia 12345:67 khong con du, ta phai b d t d s 6 b j chia di 17 don vi.
Nhom 2.-0e phep chia 12345:67 khong con du, ta phai them vao so bj chia 67 -17 = 50 don VL
Gl'.-Trong phep chia co du (a: b = q du r), ta suy ra dupc dieu gi?
HS: Thao luan theo nhom (5 phut) va neu ket qua lam viec: Trong phep chia eo dir (a: b = q du r), ta suy ra:
* { a - r)chia het cho b.
' a + ( b - r ) chia het cho b,
GV: Cac em hay van dung kien Ihuc vda rut ra, thao luan vol ban each giai 2 bai toan sau va ghi each lam vao vd:
Bai r.-Tim x, biet: 2 5 4 : x= 14 (du 16).
ea/2;ChoAlas6tunhienldnhon200.Aehlacho 6 7 d u 1 7 .
a^ Hoi A phai thay doi the nao de khi chia cho 67, ta duge phep chia khong con duvathuong tang them 2 don vj?
b) Hoi A phai thay doi the nao de khi chia cho 67, ta duge phep ehia khong con duva thuong giam di2 donvi?
G^'.'dbai 1, HS datim dupc x = 17, em conhan xet gi ve sochia va so du?
WS.-So du be hon so chia 1 don vj va day la so du Idn nhatcua phep chia,
GV: Cac em hay van dgng kien thuc do vao giai bai toan sau:
S a / 5 ; M g t p h e p c h i a c 6 d u , e6s6ehiab§ng25, thuongb^ng23vas6dulasodulcmnhat.Timsob!
chia trong phep chia do.
Em va ban doi vd, chua bai cho nhau.
G / ; Dudi day day la mgt so bai toan trong thucte cugc song hang ngay, nhdng bai toan vui, toan do lien quan den phep chia co du, cac em hay suy nghT each giai de chuan bj cho tiet hgc sau.
Ba/4.-Khoildp4cuaTn/dngtieuhgcDoanKetc6
(ki2'7/2014)
* Phong Giao due tieu hpc, Sd Giao due - Dao tao Ha 1^nh
Tap chi Giao due so 338 | 47
so HS trong khoang tCr 150 den 250 HS. Khixep hang 2, hang 5 deu thieu 1 HS va khi xep hang 9 thi vda du, Tinh so HS khoi 4 cua Ta/dng tieu hgc Doan Ket.
Sa/5;Mpt ngudi hoi anh chang chan ciiu: "Anh CO bao nhieu con cuu?". Anh chan ciiu tra ldi: "So cuu eua toi nhieu han 400 eon nhung khong qua 900 con Neu ehia so cuu cho 9 thi d u 3 , chia cho 6 cung du 3 con chia eho 25 thi du 19". Hoi, anh do c6 bao nhieu con ciru?
ea/5;Ba anh B^c, Trung va Nam ciing lam viec eho mpt eong ti, Cusau 5 ngay lam viee thi anh BSc dupc nghi 1 ngay, sau 6 ngay lam viee thi anh Trung dupc nghi 1 ngay va sau 7 ngay lam viec thi anh Nam dugc nghi 1 ngay. Hom nay la thu sau la ngay nghi eua anh Bac, ngay mai la thL? bay la ngay nghi cua anh Trung va ngay kia Chunhat la ngay nghi cua anh Nam. Hoi it nhat sau bao nhieu ngay ketdhom nay ba anh se eo eiing ngay nghi va hom do la thd may?
Bai 7: l\/lgt nha giao bi ke gian len vao lay trgm thocdbon cot, chi con lai dcot thu nhat: mgt dau thoc va mgt cai noi, dcot thdhai: ba dau thoc va mgt cai ra, d cot thir ba: nam dau thoc va mgt cai chau, d cot thu tu: bay dau thoc va mgt cai thiing, Bon ten trgm Ti, Sdu, Dan, Mao bj bat giai len quan. Ten Ti khai da lay thoc bang noi, ten Suu khai da lay thoc b§ng ra, ten Dan kiiai da lay thoc bang chau, ten Mao khai da lay thoc b^ng thiing, moi lan ehiing deu dong day thoc bdi eae dung cu tren. Khi eho dong lai thi noi chua dung 3 dau thoc, ra ehu'a dung 5 dau thoc, chau ehua dung 7 dau thoc, con thung chda dung 9 dau thoc, Biet so th6c d moi cot b i n g nhau, nhieu hon 300 dau va it hon 400 dau. Em hay lam thd "Bao Cong xuan"
xac djnh mdi ten trgm da lay bao nhieu dau thoc de Chung phai "tam phuc, khau phue" nhe.U
Tai li^u tham khao
D6 Dinh Hoan (chii bifin). To^n 4. NXB Gido due Viet Nam, H. 201 \.
SUMMARY
For teachmg session 2 according to the direction trai experimental. Idiam pha lesson "Luyen for allowed chia cho numbers are 2 digit". Posts of this mentioned one way to the teaching session 2 lesson "Luyen for allowed numbers are 2 digit" out of grade 4 according to the direction teachers Foundation for student trai experimental, kham pha: - Start, also comments ex- pressions the education: Through the game, create student both also comments e?q)resslons the students:
- Trai experimental, kham pha: From a legal compute bay token in SGK. teachers the said the problem then instrucUon, student as many orientation equal to acti- vate Preferences, create.
Day hpc Iheo hudng phat trien...
(Tiep theo trang 41)
bay ketquathi nghiem, rutra ket luan vetinh chat cua nucfc, G V y e u cau HS neu ra mot so hien tupng va dng dung tinh chat nay cua nudc trong tU nhien, san xuat vadPi song,
3) Phit trien eie NL khac. Biing each to chire hpe tap theo kieu "Trung bay - trien lam" hay "Trai nghiem - cugc sdn^', GV da tao dieu kien eho HS dupc bge 16 kha nang cua minh, Th6ng qua hoat dong hgc tap nhieu NL cua HS dugc hinh thanh va the hien: NLtuhoc, tunghlen cuu tim toi, kha nang tu duy sang tao; NLthuc hanh, thi nghiem, NLIien he thuctiencu6cs6ng;NL hoat dgng nhom, NL thuyet trinh; NL danh gia va tudanh gia va nhung NL khae.
3. Cach day hgc chi tap trung trang bj kien thu'c cho ngudi hgc can dUpc thay thebang each tochdc day hpc hudng tdi viec ren NL cho HS.Tddo, giiip HS biet each chu dpng tu hgc va hpc theo nhom, van dung kien thdc vao thuc tiln, hinh thanh NL tuquan ban than va tuquan theo nhom, ldp. Do la nhung bien phap thiet thuc gop phan nang cao chat lugng giao due toan dien HS, giao dye li tudng, truyen thong, dao dire, loi song voi NL va kTnang thuc hanh. Van dung kien thde vao thuc tien se mang lai chat lugng va hieu qua giao due, dong thdi, tao dieu kien va thiic day phat tnen kha nang sang tao, tu hgc va khuyen khich cac em hoc tap suot d d i , •
Tai li^u tham khao
1, Bo GD-DT. TynhiSn - Xa hoi va phuong ph^p day hoc Tii nhien - Xa hoi (tap 2). NXB Gido due, H.
2007,
2, B6 GD-DT, Ddi m m phinmg phap day hpc d'ti^u hoc. NXB Gido di^c, H, 2006.
3, BO GD-DT. Tu-nhien - Xa h6i lop 1,2,3. NXB Gido due, H. 2008.
4, BO GD-DT Khoa hoc Iti-p 4, 5. NXB Gido due, H 2008,
SUMMARY
Extraction methods used, reasonable teaching institutions to promote positive self dominate knowl- edge, develop quality, learner competence. That ca- pability and practical skills, knowledge and use real- world connections. Ability ta develop Innovative, self- learning, self-exploration of life in the environment lively and practical. The capacity that the study of Nature - Society Is considered the primary potential to harness and arouse the passion, the excitement of student learning.
