Sometimes it is hard to let students collect data to test their ideas about nature. For example to make observations how stars move for a long time, or do experiment about why plant grow to the sunlight. In this case, when oboservation and experiment difficult to carry out in classroom, computer software or interactive simulations can help a lot. There are two examples.
In a middle school biology class, students can play with the following flash game to figure out why plant grow to the sun.
Recently I attended Dr Luft’s class Methods of Science Teaching. I am becoming more and more interested in Modeling activities and I want to make a collection of these activities.
This is the list:
These activities provide lots of practice options for science teachers. We usually only provide standards of what students should master but little practice activites for teachers. Well, the Next Generation Standard is going to change this.
Reflections on Modeling in science teaching
The charm of modeling:
What to focus in the modeling activites as a science teacher?
How to keep the balance between knowledge-centered and student-centered? Individual and Community? Cognition and metacognition?
Welcome to join the discussion of these open questions!
A good teacher just like a good cook. Of course, you can tell a good cook by the taste of his dishes. So students’ perfect performance is a good predictor of competent teacher. But it takes a lot effort to make the dishes OR evaluate the students. In fact, we can also tell a good cook by his preparation and operation of his cooking. Good cook can aways make many dishes in a limited time. Because he don’t stop, when heating the water, he is washing the vegatables or cutting the meat. When the water is ready he is also ready to fry them together. The teacher do the same thing in class expecially in a short class. I found this metaphor visiting Dr C’s class, she give instructions as well as preparing the tools for modeling, at the same time she was also doing demonstration of what the secret tube behaviors.
Sometimes science teacher educators complain that teachers’ beliefs are stubborn and reluctant to change their practices. Well, It is true.
The science teacher is like a swimming player in a swimming poor. The science teacher educator stand beside and tell the player how to swim, which style is good which is bad. But the most important thing for a person in the swimming poor is to keep safty and the most reliable style is his primary style. How can we blame them not trying to change, if their safty is not guaranteed and skills not developed.
As a science teacher educator, you can not stand by but jump into the swimming poor and provide necessary skills and safety.
It is my first time to view a science classroom teaching in Japan. In fact, it supprise me a little. I know the science education in Japan is of high quality. They get much better score than the other counties and teacher are respectable profession. But I never thought the classroom are so interactive and effective. You can click here to view the video.
This eighth-grade science lesson is about the formation of clouds. It is the third lesson in a sequence of 19 lessons on weather. The lesson is 53 minutes in duration. There are 25 students in the class.
http://timssvid1.s3.amazonaws.com/JP5%20Air%20compression%20and%20expansion.mp4
Here is my record of the time usage of the class:
00-03 Review what they learn
03-07 Demonstration
07-17 Demonstration of key skills for today’s experiment
18-36 Student activites(4 experiments and group take turn)
36-50 Sumary of experiment result and draw conclusion
50-52 self-evalation
I watched the video twice, first I just got a glance of it very quickly. The second time, I watch it very carefully and make notes of what teacher and students were doing.
First, I found a very interesting thing that the Japenese teacher used about 17 minutes to engage students and make demonstration at the begining. He also used about 17 minutes to sumary the results and conclusions at the end of the class. Acording to psychology studies, people are most likely to remember what happened at begining and at the end. People usually can only concentrate for 15 minutes. So most TED videos will not last more than 17 minutes. I don’t know if the teacher did it popurely. But he did it really well.
Second, the class is very interesting and vigorous. Students really had fun with the activities and record and try to explain.
Third, it keep a good balance of knowledge-centered and student-centered. The most important ideas and inquiry skills were embodied in student activities.
At last, I want to say although the teacher said nothing about modeling. But he raised a question for students to study. Students want to explain but had little idea and experieces. So they did the activities that teacher prepared for them. Before experiments, they make their explannation and predictions, they recorded the result on the handouts, they have to revise their explanation and building a more powerful causal model to explain all the phenomenons. So we do can found the shape of modeling in this class.
One of the most deep impressions I got of US is the pursuing of simple and comfortable life.
First is the bus design.
There is a button out side of the bus that customers can push to kneel the bus. Another design is that there is a string along the windows. You can pull the string to let bus stop. You don’t even need to stand up.
Another interesting thing I discovered the yellow alert along the road. First I though it is to let people wark accross the street. But when I look into it carefully, It said “State law: stop when human on the line”, it is for the car. No wonder evertime when I was on the line, the drive will stop let me pass first. What a nice law!
One day, when I was on my way home from supermarket, I found there is an American Bank ATM special for car drivers near the shops. I have never saw such ATM before in China. You don’t have to get out of your car when you using the ATM In China, when you go to banks, usually you have wait for half an hour to get your turns in Shanghai. Why it is so different! This is a really good question to think about.
The last discovery is kitchen. They have kitchen not only in the apartment where I live but also in the office. There is a special kitchen room for professors and students to heat their lunch or make coffee. So nice!
Oh, I nearly forget. The water purifier. It is so cool and useful, I love it too much.
It is evident that the goal of American people is to pursue a simple and comfortable life. Maybe not very luxurious but comfortable.
How did they achieve that, market and competition may be the driving power. What it doesn’t happen in China? Big question!
Sometimes you want to run away confronting a challenge. Usually, you have your own reasons. It is too hard. It is too boring. I am not good at this. It is so painful. You want to advoid to meet it although it is important and urgent. We all know it but feel so hard to control yourself.
So what to do?
YOU have an imaginary enemy to fight. Game start! Sometimes your enemy is strong and sometimes he is endurable. Mostly, you have exaggerated your enemy and belittled yourself. Imagine you are fighting against an enemy who also have his own weakness. The wise move would be found his weakness and take all the advantage you have to beat him. If you don’t fight, you are doomed to failure. If you fight, there still a hope to win.
In fact, you have no opotions but to fight. Your imaginary enemy would alert you and help you to beat the fearness and win the game!
Recently I found some useful tips to get things done more effectively.
How do you capture your screen when you are watching a vedio without stop it.
After type your keyword in the address bar, how do you google it in a new tab with Chorme browser?
These days while I live in my apartment, I pay close attention to the daily life of people here. I have drawed a conclusion: Americans are lazy.
In fact, Lazy here is not used in a derogatory sense. You know, only the lazy people can invent and design a comfortable life. Americans are such kind of designers who are persueing simple but comfortable life. Let me give you some examples.
I live in a house department. In China, the parking area is often underground or a little far from the appartment. But in USA, the parking lot is jut in front of the hourse near the door. You can imagine when you get back from work, get out of your car, and then enter your door, it is so convinent.
After you get in, you can find a kitchen, a sitting room, a laundry room and a bath room. If you take a look at the kitchen, you will find a dish washer there and microwave oven. In China, most people just wash by hands, you can hardly found a dish washer, expecially in a student’s department.
As to food, most food can be cooked just by heatting, like milk and bread. If sauces are needed, they are already mixed up and ready for use. You can find all this kind of mixed up sauces or semi-manufactured food everywhere in a food supermaket. Cooking become easy here, athough the taste may becoming a little dull. Most Chinese will not buy the mixed sauces, they may want to make their own although they will spent a lot of time on cooking.
One day, a ceaseless noise of machinery wake me up. I look out through the window, I found a man is using a grass cutter in front of the door. In China, people also use this kind of grass cutter, which is belted to the waist. But lawn mower like a car is hardly found in China. I often saw an american sitting on it and drive it on the lawn, it is fun. I also found people here clean the street in a differnt way, they use a air blower to blow the leaves away and make the road clean. If you walk on street in the early morning in Beijing, you will see a cleaner clean street with broom. You will never found a man with a blowing machine walk here and there.
And almost everyone have a car here. Once I ask a black man for directions, after telling my the way, he said don’t you have a car, I sait not yet. He then added while it will be 20 to 30 minutes’ walk. I follow his directions, after 10 minutes I got there. It is not that far, I said in my mind. May be they drive too much, and then have no idea how long it will take by walking.
So there are so many differences between the two countries. It also stand for different culture. The Americans are taking every advantage of modern science and technology to make their lives simple and comfortable. Labor is much more expensive in USA than in China. The Chinese culture advocate deligent, hard-working and Obedience. The American culture advocate Science & Technolgy, comfortable life and freedom. You can not say which one is better, but they can learn from each other. Athough the American life is easy and comfortable, but it exhausted much more energy. Athough, Chinese food is delicious, but it is time cousuming, I think Chinese really should spend more time on inovation in S&T and social system.
by chunlei 08/02/13 07:30AM
I had a dream today. I took a flight back to home just in order to make sure everthing at home is Ok. I don’t konw why. There is an old saying what you dream at night is what you think at day. Maybe I am a little homesick now. When I am awake, I am laying on a big white bed still in USA. I thought I will not easily be homesick, but I am wrong. Well my advisor is right, I will confront some hard time and even shed tears. If it was the Cost, what I can do is only maximize the benifit.
I have learnt how to cook rice in microwave oven. I also learn how to cook dishes in a pan which the bottom is flat. I have been accustomed to the food here, milk and egg for breakfast, noodles or rice for lunch and supper. I improve my spoken and writing English through participting some online courses. It does work.
I will also record what I have done, observed and thought by bloging. It will cover all the stories that I experienced during my study in USA.
by chunlei 08/02/13 05:41 AM
使用Python已经有几年了，也写过很多文本分析的程序，包括输入输出，写文案，抓网页等。最大的体会是Python的简洁性，你可以用最好的代码做最多的事儿，前提是你知道怎么做。Python可以让你实现人工智能、大数据分析、网页开发，几乎无所不能。所以，如果你想进入码农行业，你要认真的考虑一下是否要学习Python。
本文列举了个人常用的命令，并不系统。后面期望不断改善。
Python重要用法示例
dir(list)#显示关键字相关的函数
help(list.reverse)#查询某个函数的功能set 让一个list变成无重复元素的set
例如：
shapes = ['circle','square','triangle','circle']
setOfShapes = set(shapes)
setOfShapes
set(['circle','square','triangle'])
setOfShapes.add('polygon')
'rhombus' in setOfShapes
False
setOfShapes - setOfFavoriteShapes
setOfShapes & setOfFavoriteShapes
setOfShapes | setOfFavoriteShapes map和lambda
map(lambda x: x * x, [1,2,3])
[1, 4, 9]
filter(lambda x: x > 3, [1,2,3,4,5,4,3,2,1])
[4, 5, 4]Object 先定义一个类，然后给类生成实例
定义如：
class FruitShop:
def __init__(self, name, fruitPrices):
"""
name: Name of the fruit shop
fruitPrices: Dictionary with keys as fruit
strings and prices for values e.g.
{'apples':2.00, 'oranges': 1.50, 'pears': 1.75}
"""
self.fruitPrices = fruitPrices
self.name = name
print 'Welcome to the %s fruit shop' % (name)
def getCostPerPound(self, fruit):
"""
fruit: Fruit string
Returns cost of 'fruit', assuming 'fruit'
is in our inventory or None otherwise
"""
if fruit not in self.fruitPrices:
print "Sorry we don't have %s" % (fruit)
return None
return self.fruitPrices[fruit]
def getPriceOfOrder(self, orderList):
"""
orderList: List of (fruit, numPounds) tuples
Returns cost of orderList. If any of the fruit are
"""
totalCost = 0.0
for fruit, numPounds in orderList:
costPerPound = self.getCostPerPound(fruit)
if costPerPound != None:
totalCost += numPounds * costPerPound
return totalCost
def getName(self):
return self.name调用winsound 函数
import winsound
# press a make a beep
if event.KeyID==65: winsound.Beep(200,9)
# press ESC play exit sound
if event.KeyID==27: winsound.PlaySound("SystemExit", winsound.SND_ALIAS)
使用pyHook监听鼠标和键盘事件
import pythoncom
import pyHook
def onKeyboardEvent(event):
global switch
# 监听键盘事件
if switch:
print "Key:", event.Key
print "KeyID:", event.KeyID
return True #监听函数的返回值
def main():
# 定义一个实例
hm = pyHook.HookManager()
# 监听所有键盘事件
hm.KeyDown = onKeyboardEvent
# 设置键盘监听器
hm.HookKeyboard()
# 循环并保持一直处于监听状态
pythoncom.PumpMessages()
用pyenv的基本操作命令管理python版本
pyenv versions# 查看当前已安装的 python 版本
pyenv install ... #安装指定版本的 python
pyenv global python版本 #切换全局 python 版本
source ~/.bash_profile
pyenv local python版本 #切换当前文件夹下的 python 版本
pyenv shell python版本 #切换当前 shell 中的 python 版本
pyenv version #查看当前使用的 python 版本python 数据库开发
取消所有8000进程：
sudo lsof -t -i tcp:8000 | xargkill -9
创建项目
django-admin startproject demoproject
创建应用
cd demoproject
python manage.py startapp TestModel
打开 mysql服务器
mysql -u root -p
参考：手册
现在我们可以创建数据库表了。首先，用下面的命令对校验模型的有效性：
python manage.py validate模型确认没问题了，运行下面的命令来生成 CREATE TABLE 语句：
python manage.py sqlall books
python manage.py syncdb打开服务器
python manage.py runserver
python manage.py migrate
python manage.py makemigrations
查看sql服务是否启动
ps -ef | grep mysqld#查看MySQL服务器是否启动
service mysqld status#查看服务运行的状态Mysql
mysql -u db_user -p
SHOW DATABASES;
CREATE DATABASE blog_data;
drop database mydb;
SHOW DATABASES;
Whenever you’d like to exit MySQL server, press CTRL + D.
show variables like ‘%char%’;
set character_set_server=utf8;
set character_set_database=utf8;
show variables like ‘%char%’;
ALTER DATABASE classlinkr DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci
use my_db;
show tables;
show full columns from clips_clip;
ALTER TABLE classlinkr.clips_clip MODIFY COLUMN concept VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL;
闲来无事，随便看看Python 3.0的文档，发现了一个很pythonic的模块：声音播放 for windows；凑个流行语叫做“很傻很天真”，不过挺好使得。
1 winsound.Beep
每一个都有不同的用法，一个一个来看吧。
winsound.Beep(frequency, duration)PC扬声器滴的一声，就是它了。第一个参数frequency表示分贝数，大小在37到32767之间。第二个参数是持续时间，以毫秒为单位(有耐心的话可以试试winsound.Beep(32767,9999999)，嘿嘿)。
2 winsound.PlaySound
1. import winsound
2. # Play Windows exit sound.
3. winsound.PlaySound("SystemExit", winsound.SND_ALIAS)
4. # Probably play Windows default sound, if any is registered (because
5. # "*" probably isn't the registered name of any sound).
6. winsound.PlaySound("*", winsound.SND_ALIAS)
不过只能播放wav,不能播放wma和mp3文件，这2种还需要其他包的支持。网站维护：
使用Django框架
前端口用h5和JS开发
替换该文件之后，需要跑一下systemctl restart httpd命令才能生效