Interactive Greatest Common Factor Activity

The new interactive greatest common factor activity at helps students master the process of finding the greatest common factor. This interactive activity can be used as either an online or offline activity. In the online mode student can enter their answer directly in the activity and the computer will tell them when they have the correct answer. They can keep changing their answer until they get it correct. This will help students master the process of finding greatest common factors. The page starts out with 6 problems and more problems can be added.

To use the offline mode simply print the page and the computer takes care of making sure that it is nicely formatted. After you have printed the worksheet make sure to click the answer key to fill in all of the correct answers and then you can print your answer key. Both the worksheet and answer key have the same timestamp to help you keep track of which answer key goes with which worksheet.

The program makes sure that their are no duplicate questions.

Tips for finding greatest common factors. 
Find the factors of each number just as described in the factors activity the largest number in both lists is you answer.

Make a factor tree of both numbers and cross out the leaves not in both trees. Multiply the leaves in one tree together and that is your greatest common factor.

Example:
Find the GCF of 12 and 16.

Factor Tree of 12  2 × 6 2 × 2 × 3 Common leaves 2 × 2 × 3

Find the GCF of 16 4 × 4 2 × 2 × 2 × 2 Common leaves 2 × 2 × 2 × 2

Multiply the common leaves together: 2 × 2 = 4. Therefor the greatest common factor is 4.

Remember the tips for finding factors 2 through 10.
2: If the last digit of the number is even (0,2,4,6,8)then then number is divisible by 2.

3: If the sum of the digits is divisible by 3 then the number is divisible by 3. For example 21 would be 2 + 1 = 3 which is divisible by 3 so 21 is divisible by 3.

5: If the last digit of the number is 5 or 0 then the number is divisible by 5.

6: If the number is divisible by 2 and 3 the number is divisible by 6.

10: If the last digit of the number is 0 then the number is divisible by 10.

Interactive Finding Factors Activity

The new interactive factors activity at helps students master the process of finding factors. The interactive factors activity can be used as either an online or offline activity. In the online mode student can enter their answer directly in the activity and the computer will tell them when they have gotten the correct answer. They can keep changing their answer until they get it correct. This will help students master the process of finding factors. The page starts out with 12 problems and more problems can be added as they finish.

To use the offline mode simply print the page and the computer takes care of making sure that it is nicely formatted. After you have printed the worksheet make sure to click the answer key to fill in all of the correct answers and then you can print your answer key. Both the worksheet and answer key have the same timestamp to help you keep track of which answer key goes with which worksheet.

The program makes sure that their are no duplicate questions. So if you limit the factors to 20 then you can have no more than 20 questions.

Tips for quickly finding factors. 
How many numbers do I need to check?
Check each integer that divides the number you are looking for the factors of until the divisor is larger than the answer.

For example when finding the factors of 20 you get the following answers.
1 / 20 = 20
2 / 20 = 10
3 / 20 = 6 remainder 2
4 / 20 = 5
5 / 20 = 4 We can stop here because the 4 is smaller than 5.

Tips for 2 through 10.
2: If the last digit of the number is even (0,2,4,6,8)then then number is divisible by 2.

3: If the sum of the digits is divisible by 3 then the number is divisible by 3. For example 21 would be 2 + 1 = 3 which is divisible by 3 so 21 is divisible by 3.

5: If the last digit of the number is 5 or 0 then the number is divisible by 5.

6: If the number is divisible by 2 and 3 the number is divisible by 6.

10: If the last digit of the number is 0 then the number is divisible by 10.

Graphing Resource

I just rolled out a new graphing resource at aschool.us/graphs. This new tool allows you to quickly create SVG graphs which you can then download and edit further with an SVG editor such as Insckape or Adobe Illustrator. Currently it only does horizontal, bar, and line graphs with or without grid lines. The plan is to have this website be a resource for teachers when teaching students how to make graphs and have some interactive graphs to help students learn how to read graphs.

Would love to hear any feedback.

ASchool.us Random Student Selector Update

Just got through adding two new features to the Random selectors are of ASchool.us/random. I added a menu so that you can easily see what other random script options are available. I also added a feature where you can save the list that you typed to your browser using the HTML5 local storage feature. This means that you list of names is save to the local browser and will persist across sessions, while nothing is saved on the server. Rebooting or closing your browser is not a problem. Your list will still be there if you want to use it, but you do not have to.

Subtraction & Multiplication Interactive Math Worksheets

Two more activities have been added to the series of interactive math worksheets available at aschool.us/scripts/math

• Interactive Multiplication Table:
  Simply set the size of the multiplication table and students can then fill in the answers. The computer will check their work as they go. Indicating if it is right or wrong with red and green backgrounds.
• Interactive Subtraction Worksheets
• Interactive Subtraction 1 Worksheet:
  Subtraction problems with only positive answers. Like all of the other worksheets you can check your answers as you go, print the worksheet and answer key.
• Interactive Subtraction 2 Worksheet:
  Subtraction problems with positive and negative answers. Like all of the other worksheets you can check your answers as you go, print the worksheet and answer key.

Printable Interactive Math Worksheets

Sample

The first in a series of interactive math worksheets is now available at
Interactive Addition Practice
Interactive Multiplication Practice

Features:

• Each time you visit the page a new set of problems will be displayed. 
• You can check your work as you go by typing them below the problem to see if you got the right answer or you can display all of the answers to print an answer key.
• Typing the answers online also keeps track of your current score for the worksheet.
• By default 1 row of problems are shown but more can be added a row at a time. 
• The worksheets are also very print friendly, in that they remove all excess instructions, links, etc.... 
• You can adjust the size of the problems at the top of the page.

Please leave suggestions on how to improve these pages. 

Over 1,000,000 math fact problems solved!

We are excited to share that over 1 million math fact problems have been solve at aschool.us/math. Over 880,000 of them were solved correctly giving a student an accuracy of 86%.