Interactive
ABCya

Ab Cya: Robo Trobo

For Students 3rd - 6th
Robo Trobo is a problem solving game for kids of all ages. Kids will need to guide Robo through complex puzzles in order to complete the different levels. Have fun and think outside the box!
Interactive
Math Slice

Math Slice: Smart Guess Game

For Students Pre-K - 1st
Can you guess the correct number between 1 and 99 in less than 30 tries? Play this fast paced, interactive game that tests your number sense and reasoning skills. If your are a great guesser, your name will be posted.
Activity
University of Cambridge

University of Cambridge: Nrich: Cubes Within Cubes

For Students 3rd - 4th
On this one page website sharpen your logic, geometry, spatial thinking, and problem solving skills while working on this challenge. The solution is available to double check your solution.
Lesson Plan
PBS

Pbs Mathline: Bead Dazzling (Proportional Reasoning) [Pdf]

For Teachers 3rd - 8th
A comprehensive instructional activity on algebraic thinking where students create and identify patterns using proportional reasoning. Research based, this instructional activity includes technology connections, items for discussion, and...
Interactive
Other

Puzzle Parlor

For Students 9th - 10th
Find a collection of colorful, interactive, challenging puzzles: Hexnut Jr., Quintapaths, Roundominoes, and others.
Unit Plan
NASA

Nasa Smartskies: Line Up With Math: Math Based Decisions in Air Traffic Control

For Students 9th - 10th
In association with NASA, LineUp With Math presents problem sets which 'enable students to explore and apply decision-making and reasoning skills, specifically to resolve distance-rate-time conflicts in air traffic control'. An...
Unit Plan
Texas A&M University

Wtamu Virtual Math Lab: Beginning Algebra

For Students 9th - 10th Standards
This tutorial for students new to algebra provides explanations, definitions, examples, and practice problems. The practice tests cover topics such as real numbers, fractions, equations, graphing, and exponents.
Activity
Maths Challenge

Maths challenge.net: Right Angle Reasoning

For Students 9th - 10th Standards
A geometry problem for students to use their mathematical reasoning skills to explain a right triangle property.
Activity
University of Cambridge

University of Cambridge: Nrich: Amy's Dominoes

For Students 3rd - 8th
On this one page website sharpen your logic and problem solving skills while working on this challenge. The solution is available to double check your solution.
Interactive
University of Cambridge

University of Cambridge: Nrich: Game Fifteen

For Students 1st - 5th
Sharpen your problem solving and strategy skills playing this interactive game, Fifteen. The rules are simple but the game requires some thinking if you want to beat the computer. There is a "Printable Page," link if you want to print it...
Activity
University of Cambridge

University of Cambridge: Nrich: Mixed Up Socks

For Students K - 1st
Your reasoning skills will come in handy as you find solutions to these "sock" problems. Solutions are available on this one page website.
Interactive
University of Cambridge

University of Cambridge: Nrich: Game Pumpkin Patch

For Students Pre-K - 1st
Sharpen your problem solving and strategy skills playing this Somali game, Pumpkin Patch. The rules are simple but the game requires some thinking. There is a "Get Printable Page," link at the top to print out the materials you need.
Activity
National Council of Teachers of Mathematics

Nctm: Figure This: Tan, Don't Burn

For Students 3rd - 8th
How about a math challenge for a sunny day at the beach? Apply your problem solving, number sense, and logical reasoning skills to find out how long it would take Helix to get sunburned using SPF 10 lotion. Discover why understanding...
Activity
University of Cambridge

University of Cambridge: Nrich: A Flying Holiday

For Students 3rd - 8th
Some may think this problem is for the birds but you will need to use your problem solving skills to come up with a reasonable answer. Then check this one page website for the solution.
Interactive
University of Cambridge

University of Cambridge: Nrich: Game Counter Roundup

For Students K - 1st
Sharpen your problem solving and strategy skills playing this interactive game, Counter Roundup. The rules are simple but the game requires some thinking if you want to beat the computer. There is a "Get Printable Page," link at the top...
Interactive
University of Cambridge

University of Cambridge: Nrich: Two Stones Game

For Students Pre-K - 1st
Sharpen your problem-solving and strategy skills while playing the interactive game, Two Stones. The rules are simple, but the game requires some thinking if you want to beat the computer. Watch as the play proceeds to see what it takes...
Interactive
University of Cambridge

University of Cambridge: Nrich: Daisy Game

For Students Pre-K - 1st
Sharpen your problem solving and strategy skills by playing this interactive game. The game's rules are simple, but play requires some thinking if you want to beat the computer. You can change the settings and see if your strategy works...
Interactive
Other

Websudoku

For Students 9th - 10th Standards
A fun puzzler to get any mind thinking logically! Try many levels of puzzles using the following rules: "Enter digits from 1 to 9 into the blank spaces. Every row must contain one of each digit. So must every column, as must every 3x3...
Activity
National Council of Teachers of Mathematics

Nctm: Figure This: Pigeonhole Principle

For Students 3rd - 8th
What is the possibility that another student in your school will have your exact same initials? Try this math challenge using logical reasoning and the "Pigeonhole principle," to discover how this could actually happen. An engaging...
Activity
Maths Challenge

Maths challenge.net: Children in a Circle

For Students 3rd - 6th
A "one star" geometry problem that requires problems solving skills where drawing a picture might help with the answer.
Interactive
Iowa State University

Math Night Resources: Pencil and Paper Games

For Students 3rd - 8th
Play these pencil and paper games to engage learners in critical thinking and reasoning. Written directions are provided along with colorful animation to explain in detail how each game is played and possible strategies needed to win.
Lesson Plan
University of Canterbury

University of Canterbury: Cs Unplugged: The Turing Test

For Teachers 2nd - 8th
Explore how we might recognize whether a system is truly intelligent. It involves reasoning about what it means to be intelligent, and even what makes us human.
Unknown Type
Khan Academy

Khan Academy: The Honest Truth About Dishonesty

For Students 9th - 10th
This is a four-problem practice question for the CARS test using the article "The Honest Truth about Dishonesty."
Unknown Type
Khan Academy

Khan Academy: The Happy American

For Students 9th - 10th
This is a four-problem practice question for the CARS test using the article "The Happy American."