CK-12 Foundation
Ck 12: Elem Math: Mixed Operations Selecting the Incorrect Sentence
[Free Registration/Login may be required to access all resource tools.] The video shows how to add and subtract three digit numbers with two operations in a number sentence to determine which number sentence does not match the correct...
CK-12 Foundation
Ck 12: Elem Math: Fact Families Numbers to 1000
[Free Registration/Login may be required to access all resource tools.] The video shows how to determine the missing number sentence when adding and subtracting 3-digit numbers by using fact families.
Alabama Learning Exchange
Alex: 100 More Hungry Ants
Students will investigate what happens to the number of ants at a picinc when 100 more ants arrive at the picnic. They will explore this concept using a slide presentation followed by a partner game. This lesson plan was created by...
University of Illinois
University of Illinois: Mste: Flash Card Applet
In this activity, students solve addition or subtraction of one- and two-digit numbers as their progress is checked.
Toy Theater
Toy Theater: Math Test
You choose the type of math test you want to take: addition, subtraction or multiplication. Then decide how many digit you want in your problem. Click "Start" and type in the answer. Click "Next" to get the next problem. It keeps track...
Illustrative Mathematics
Illustrative Mathematics: 4.nbt What's My Number?
The purpose of this task is for students to reason about base-ten numbers on the number line in a way that will require them to use what they know about place value. Students first represent addition and subtraction on the number line in...
CK-12 Foundation
Ck 12: Elem Math: Adding and Subtracting Three or More Numbers
[Free Registration/Login may be required to access all resource tools.] This is a set of practice problems where students are given word problems where they have to add or subtract 3 or more 1-digit numbers.
Khan Academy
Khan Academy: Add and Subtract on a Number Line
Practice adding and subtracting numbers like 554 and 237 using a number line. All numbers are less than 1000. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.