Lucky Numbers Math Game for Kids (Decimal Place Value + Probability)

Back in my teaching days, I loved playing games with my students. It's such a fun way to introduce or reinforce a concept. I particularly enjoyed math games, as did the kids. One of our favorites was one I called Lucky Numbers. 

The beauty of Lucky Numbers is that you can play with any size group - we regularly played as a whole classroom. A single round is really short, so you can squeeze in a game in the awkward three minutes before dismissal, or during a 10-minute rainy day recess. All you need is a single 10-sided die (affiliate link here and below). 

Before I get to the game, I have to talk about kids and dice. Kids LOVE dice. Every single student I ever had liked playing with ordinary 6-sided dice. When I pulled out the 10-sided dice or the fraction dice, they'd go nuts. Kids who weren't ordinarily engaged during math time were practically falling out of their seats waiting for me to pass out the special dice and teach them the game we'd be playing. I never thought to do it, but honestly, I should have bought a bunch of dice and used them as rewards. Or a fundraiser! If I'd thought to have my students sell sparkly 10-sided dice back in the day, we could have paid for all of our field trips. These colorful 10-sided dice cost less than 13 cents a piece. I guarantee you we could have easily sold them for a dollar a piece. And if we'd done a blind purchase, where you pay your dollar to reach into the bag and pick a random color, we could have sold even more as people tried to get their favorite colors. 

Anyway, on to the game. The objective of Lucky Numbers is for students to learn decimal place value to the hundred thousandths, to understand what each position means, and to be able to accurately read a number with a decimal place. To play, each student needs a piece of paper and something to write with.  

On the chalkboard, draw a number of lines representing how many digits are in the target number. Around 5 is best. Have the kids copy this onto their paper. As an example, let's start with a number with three places to the left of the decimal points (hundreds) and two to the right of the decimal (hundredths). 

Roll the die and announce the number. (These huge dice are a hit in the classroom.) All players need to write that digit into one of the empty positions, trying to make the largest number possible. So if the digit is 9, the smartest location to put it is in the hundreds place. If the digit is 0, you'd put it in the hundredths place. Those are obvious - the other digits take some logic and some luck!

Here's a game in progress. Our pretend classroom is on our fourth round of the day. The student did great on their first round. 96.837 is a high number, but anyone who put the 9 in the tens place and the 8 in the ones place will beat it. The second round did not go well for this student, who was betting on a high digit coming up for the hundreds place and ended up with a 3. (Once a digit is written, you can't move it). In the third round, the student got the fourth highest possible number (9.820 would win, 9.802 and 8.920 would beat it). 

In the current (fourth) round, our pretend student put the four in the ones place. This is a good move. The next roll was a 5, which they put in the tens place. Now there's a three. Where should it go? Do you put it in the tenths place and hope that the next two rolls are higher than 3? Statistically speaking, yes, that's what you should do.

After the final roll, there are always immediate groans and cheers. After writing in my final digit, I would model how to read my number, then call on students to read their numbers. I emphasized using the place value chart to help them say the number correctly, which included saying "and" for the decimal point instead of "point." So 8.902 should be "8 and 902 thousandths" not "8 point 902." 

Anyone who scored higher than me AND could correctly pronounce their number (with help, if necessary) would earn a point. If I got the highest possible number, I earned the point. The points didn't really matter, of course, but the kids always got a kick out of beating me. And I got a kick out of seeing them learning while having so much fun.