Everyday Math: Grocery Store Math

We went on a field trip this morning to....Wal-mart and our local discount grocery store.   Armed with my list (no camera)  and calculators for each child, we were ready to calculate. 

Here's a list of all the math tasks we did between the two stores:

Wal-mart we used calculators to find the following:

• Calculated unit price 
• Added up each item to find our total
• Multiplied to find sales tax and added that to our total to find the total price.
• Compared unit prices between sizes of the same product
• Compared the total on our calculator to our actual price  (Daniel was only about $2 off --over)
• Talked about why our price was over/under the actual price
• Looked at the receipt to find the actual prices of things we had to estimate (things that weren't labelled, produce)
• Talked about why it's important to know how much you're spending (cash only or staying within your budget)

We could have compared prices between brands to see what was a better deal, but I didn't think of that at the time.  

At UGO, we left the calculators in the car, so I told the kids we were going to estimate our purchases:

• Weighed fruit to get the price
• Rounded each item 
• Added it to our running total
• Calculated sales tax by rounding it to 10 and multiplying
• Added sales tax to the end total
• Made an impulse purchase and did last minute calculations
• Made an educated guess based on our running total to the actual price of our purchases (Tera was closest- $2 under; Daniel $4 under)
• Talked about importance of estimating over your purchases to make sure you have enough money
• Discussed the possibility of "what if we had only cash and had to put something back?"  What would they choose?  
• Discussed needs vs. wants in regards to what we'd put back

This is not something I do on a regular basis, but this week we've covered unit price, sales tax and money.  It fit perfectly with our math curriculum.  I'm sure there are other ways we can incorporate math into our every day lives. 

My favorite part was when the cashier at UGO asked us if we home schooled .  I explained to her we were doing part of our math on the go today and the kids were guessing what our total would be.  She played along with our guessing game by making a big deal of pushing the total button and then asking the kids which one got the closest.  

I'll be looking for more opportunities to incorporate Everyday Math into our everyday life.  (Next time, I'll take my camera!)

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