Topics: Addition, subtraction, estimation, comparisons. Materials: Card deck, pencil and paper, white board/document camera. Grades: 2, 3, 4 Common Core: 2.NBT.B.5, 3.NBT.A.2 How close can you get to the target number with the digits provided? Why We Love Horseshoes Horseshoes combines arithmetic practice with complex thinking. Students make their own choices about how to combine the four numbers and get immediate feedback …

## Double Digit and Dollar Digit

Topics: Addition, Estimation Materials: A die, pencil and paper, base ten blocks (optional) Recommended Grade: 2, 3 Common Core: 2.NBT.B.5, 2.NBT.B.6 Each time the die is rolled, you can take that number of ones or tens. How close can you get to 100 without going over? Why We Love Double Digit This simplified version of Don’t Break the Bank is …

## Domino Sorting

Math concepts: Addition, Classification Equipment: Domino Set Recommended Grades: K, 1, 2, 3 Time: 15 – 45 minutes Common Core: K.OA.A.2, 1.OA.B.3, 1.OA.C.5, 1.OA.C.6, 2.OA.B.2, MP1, MP6, MP7 Overview What is the middle domino? This question launches the project of sorting the dominoes from least to greatest. Why We Love Domino Sorting Domino sorting is a perfect math challenge for a station or …

## Broken Calculators

Topics: Addition, Subtraction, Skip Counting, Multiplication, Logic Materials: Scratch paper and pencil, handouts (optional) Recommended Grade: 3, 4 Common Core: 3.OA.A.3, 3.OA.A.4, 3.OA.B.5, 3.OA.D.8, 3.OA.D.9, 4.OA.A.4, 4.OA.C.5, MP1, MP2, MP3, MP6, MP7, MP8 Something is wrong with the calculators in each lesson. Can students reach the target number despite the broken buttons? Why We Love Broken Calculators The premise is simple, but …

## Counterexamples

Topics: logic, deduction, mathematical argument, communication Materials: None Recommended Grades: K, 1, 2, 3, 4, 5, 6, 7, 8 Common Core: Variable, but especially MP3 Proving the teacher wrong. Rigorously. Why We Love Counterexamples Every kid loves to prove the teacher wrong. With Counterexamples, they get to do this in a productive way, and learn appropriate mathematical skepticism and communication …

## Blockout

Topics: Multiplication, area, strategy, addition. Materials: Crayons, Blockout game sheet Recommended Grades: 3, 4 Common Core: 3.OA.A.1, 3.OA.C.7, 3.MD.C.6, 3.MD.C.7 Roll the dice and shade in a rectangle. How can you claim the most space on the board? For 2-4 players. Why We Love Blockout This is one of those rare games that reinforces both the skill of multiplication and the …

## Square Building

Topics: Area, multiplication, number patterns , geometry Grade: 3, 4, 5 Materials: Square tiles, graph paper Common Core: 3.MD.5, 3.MD.6, 3.MD.7, 4.OA.1, 4.NBT.5, 4.MD.3, 5.NBT.5, MP1, MP2, MP3, MP5, MP6, MP7, MP8 This lesson is truly foundational. It connects central ideas of arithmetic and geometry, and advances from concrete to pictorial to abstract. It will prove to be a simple analogy …

## 1-2 Nim

Topics: logic, patterns, addition, counting, subtraction, divisibility and remainders (optional) Materials: Counters (tiles, beans, pennies, etc.) or paper and pencil Recommended Grades: K, 1, 2, 3, 4 Common Core: K.CC.A.2, K.CC.B.4, K.CC.B.5, K.OA.A.1, K.OA.A.2, K.OA.A.5, 1.OA.B.4, 1.OA.C.5, 2.OA.B.2, 3.OA.D.9, 3.OA.A.2, 3.OA.A.3, 4.OA.C.5, MP1, MP2, MP3, MP5, MP7, MP8 You can take one or two counters from the pile. How do …

## Counting Collections

Topics: Counting, skip counting, addition, multiplication (optional) Materials: Paper, pencil, objects of many types (button, beans, stones, pencils, markers, blocks, etc.) Target Grades: K, 1, 2, 3 Common Core: K.CC.A.1, K.CC.A.2, K.CC.A.3, K.CC.B.4, K.CC.B.5, K.MD.B.3, 1.NBT.A.1, 1.NBT.B.2, 1.NBT.B.2.a, 1.NBT.B.2.b, 1.NBT.B.2.c, 2.OA.C.4, 3.OA.A.1, MP1, MP6 Kids love to count things. This is a simple exercise, but a great way to get kids excited about arithmetic. Counting …

## Guess My Number

Topics: Greater than/less than, logic Materials: Whiteboard or paper and pencil Common Core: K.CC.C7, 1.NBT.B.3, MP1, MP3 Guess My Number is a quick, fun, and easy opening game to lead with a small group or the entire class. Students try to guess the number you’re thinking of in the fewest number of guesses possible. Why We Love Guess My Number …