# Mental Math Lesson Plan: Gate Game

Grade Levels: 3-5, 6-8

In this lesson plan which is adaptable for grades 5-8, students will use a free math game to construct increasingly large numbers. They will practice skills in mental math, place value, operations (including multiplication), and decimals.

### Students will:

- Build numbers using addition, subtraction, multiplication and division.
- Recognize place value from hundreds to hundredths.
- Develop mental computation skills using place value and the four basic operations.

### Materials:

- Computers with internet access for BrainPOP

### Vocabulary:

hundreds, tens, ones, tenths, hundredths, decimal, place value

### Preparation:

This lesson plan uses a free NMSU game called Gate. At the start of each level in the game, students practice building numbers to open the gate. Each of these opening screens teaches the skills students need to defeat the monsters within its gate, such as building decimals, creating numbers quickly via place value, or using a multiplier to build numbers faster.There are 16 levels in this game, and students are eventually asked to build numbers as large as 999 and as small as .01. They can use addition, subtraction and multiplication to build these numbers as efficiently as possible, they can consult the number line at the bottom of the screen and the number wheel to help them track the number they've built.

To prepare for the lesson, we recommend familiarizing yourself with game play. Students do not need specific skill reinforcement prior to game play, as they will actively construct knowledge during the game. We do not recommend having students mute the sound for game play. You can find more tips for game play in the NMSU Math Snack's game guide from which this lesson plan was adapted.

### Lesson Procedure:

- Divide students into groups and pass out Unifix cubes to each group.
- Invite students to create a color code for each cube (blue = +1, green = + 10, yellow = -1, etc.). Decide this together as a class, recording and displaying the information for students' reference.
- Write a number on the board and ask students to use any combination of cubes to construct that number. Set a timer for students to work and encourage them to talk with their group members as they make their choices.
- When time is up, invite one volunteer from each group to share how they constructed the number. Encourage students to use their knowledge of place value in their descriptions. For example, a student might say, "To create 48, I used 5 greens which are equal to 5 tens. 10+10+10+10+10=50. Then I added 2 yellows, which are each equal to -1, so that's 50-1-1. That equals 48."
- Have one student in each group choose another number, and challenge their group members to build that number using their Unifix cubes. You want to define parameters for the number range. Set a timer for several minutes and allow students to build.
- When the timer goes off, provide several minutes for students to explain to their group members how they created the number. The student who selected the number should facilitate the discussion, help group members explain their strategy clearly, and assist group members in building the number accurately if needed.
- Repeat the process so that each group member has the opportunity to choose a number for his or her teammates to build. Clean up and collect the Unifix cubes.
- Tell students they will now have the opportunity to play an online game that allows them to construct numbers and continue their practice with mental math skills as well as skills in place value and operations. You may want to display the game on your interactive whiteboard and click through the introduction screens to explain the game's premise or conduct some practice rounds.
- Provide 10-20 minutes for students to explore the game independently or in pairs.
- Ask students to briefly pause the game and participate in a whole-class discussion. Encourage students to share the strategies they used during game play, along with how they chose to place their hands on the keyboard (and why.) You can also ask students to reflect on how the number line and scale changed as they built numbers--invite a students up to your interactive whiteboard to demonstrate this if you think it would be helpful.
- Provide younger students with another 5-10 minutes of game play time in order for them to apply what they learned during the whole class discussion. For older students and those you want to continue building larger numbers and decimals, allow another 15-30 minutes of game play.
- Encourage students to revisit the game at home or later in your unit of study. You may also want to extend their learning by playing the BrainPOP movie on Multiplication or another concept you would like students to focus on based on their experience with the Gate game, such Decimals.