Helping your Child Learn Math

Mathland: The Grocery Store

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The grocery store is one of the best examples of a place where math is real. Since trips to the grocery usually affect everyone in the family, the following activities include various levels of difficulty within the activity. Look for the symbols to determine which parts of the activities are for which ages:

• for grades K-1
• for grades 2 and 3
• for grades 4 through 8.

All of these activities can take place over many visits to the store.

Index of Games and Activities

1. Get Ready
2. Scan It
3. Weighing In
4. Get into Shapes
5. Check Out
6. It's in the Bag
7. Put It Away

Getting ready to go shopping can help parents and children share their thinking strategies about math with one another.

• Paper
• Pencil
• Coupons (if you use them)

1. Involve the family in making a list. List each item and mark with checks or tallies to indicate the number needed.
   
   
2. Look at the price of an item you bought last week and intend to buy this week. How much did it cost last week? How much does it cost this week? Do you want to
   
   
   • Pay this week's price?
     
     
   • Wait until the price comes down?
     
     
   • Or, stock up if it is on sale?
     
     
3. Involve the group in deciding how much milk or juice will be needed for a week. You might decide to estimate by cups, explaining that 4 cups are equal to a quart and 4 quarts are a gallon.
   
   
4. If you collect coupons, organize them. Choose the coupons that match the items on the grocery list. Discuss how much money will be saved on various items by using coupons.
   
   

Practicing measurement and estimation will help improve your children's ability to predict amounts with accuracy.

Shopping is a part of life which really necessitates our being mathematically informed to be good consumers.

• Prices

1. Notice whether the grocery store has prices on the items or whether the pricing is dependent on scanners.
   
   
2. If there are no prices on the items, notice the prices listed on the shelves.
   
   
3. Assign each child the job of remembering the price of a few items, particularly those listed on sale.
   
   
4. Being aware of the prices of items will help you verify that the scanners are working properly and that the total is accurate when you go to check out.
   
   

The ever increasing use of technology in the grocery store puts the burden on you to beware. Your protection lies in having strong mental math skills.

One fun place to try out estimation and measurement skills in the grocery store is the produce section where everyone can have the opportunity to participate.

• The grocery scale

1. Help your child examine the scale. Explain that pounds are divided into smaller parts called ounces and 16 ounces equal a pound.
   
   
2. Gather the produce you are purchasing, and estimate the weight of each item before weighing it.
   
   
3. Use sample questions to foster thinking about measurement and estimation. You might Want to ask your child,
   
   How much do you think 6 apples will weigh? More than a pound, less than a pound, equal to a pound? How much do the apples really weigh? Do they weigh more or less than you predicted? How about the potatoes? Will 6 potatoes weigh more or less than the apples? How much do potatoes cost per pound? If they cost ___ cents per pound, what is the total cost?
   
   Some grocery stores have scales that tell all the answers to these questions, so in that case, estimate using the same procedure to make sure the machines are accurate.
   
   

Activities like this help children develop number sense for weight and foster the ability to compare items when measuring.

The grocery store is filled with geometric shapes.

• Items at the store

1. Show your child the pictures of the shapes on this page before going to the store. This will help to identify them when you get to the store.
   
   
2. At the store, ask your child questions to generate interest in the shapes.
   
   
   • Which items are solid? Which are fiat?
   • Which shapes have fiat sides?
   • Which have circles for faces? Rectangles?
   • Do any have points at the top?
3. Point out shapes and talk about their qualities and their use in daily life.
   
   
   • Look to see what shapes stack easily. Why?.
     
     
   • Try to find some cones. How many can you find?
     
     
   • Look for pyramids.
     
     
   • Determine which solids take up a lot of space and which ones stack well.
     
     
   • Discuss why space is important to the grocer and why the grocer cares about what stacks well.
     
     

Boxes, cans, rolls of toilet paper or paper towels, ice cream cones and cones that hold flowers, plus produce such as oranges, grapes, and tomatoes are all geometric shapes. Recognizing these shapes helps children connect math to the real world.

The check out counter is where we commonly think about math in the grocery store. It's where the total is added up, the money is exchanged, and the change is returned.

• All the items you intend to buy

1. Have your child estimate the total.
   
   
2. Ask, if I have 10 one-dollar bills, how many will I have to give the clerk? What if I have 20 one-dollar bills? 5? How much change should I receive? What coins will I get?
   
   
3. Count the change with your child to make sure the change is correct.
   
   

One way to make estimating totals easy is to assign an average price to each item. If the average price for each item is $2 and if you have 10 items, the estimate would be about $20.

Here's some fun estimation to do with bags full of groceries.

• Bags of groceries

1. Have your child guess how many objects there are in a bag. Ask: Is it full? Could it hold more? Could it tear if you put more in it? Are there more things in another bag of the same size? Why do some bags hold more or less than others?
   
   
2. Estimate the weight of the bag of groceries. Does it weigh 5 pounds, 10 pounds, or more? How can you check your estimate? Now, compare one bag to another. Which is lighter or heavier? Why?
   
   

This activity exposes children to the experiences of counting items and comparing qualities, as well as to judging spatial relationships and capacity. It shows how to estimate weight by feeling how much the bag weighs, comparing it to a known weight (such as a 5-pound bag of sugar), or weighing it on a scale.

Now, the sorting begins as you put away the groceries.

• Your bags of groceries
• Counter top or table to group items on

1. Find one characteristic that is the same for some of the products. For example, some are boxes and some are cans.
   
   
2. Put all the items together that have the same characteristic.
   
   
3. Find another way to group these items.
   
   
4. Continue sorting, finding as many different ways to group the items as you can.
   
   
5. Play "Guess My Rule." In this game, you sort the items and invite your child to guess your rule for sorting them. Then, your child can sort the items, and you can guess the rule.
   
   

Sorting helps children develop classifying and reasoning skills and the ability to examine data and information.