Shoppers often share their stories of cashiers rejecting legitimate coupons - frustrating and, at times, embarrassing scenes.

I recently experienced coupon rejection myself. Here's how I overcame cashiers' concerns without making a scene.

To be fair, the cashiers who rejected my coupons were teenagers working at my stores as temporary summer help. Therefore, they may not have been familiar with their employer's coupon policies.

When this happens, I politely explain to the cashier the store's policy works, and how he should enter the coupon into the store's system. When you calmly and confidently explain the store policy, the cashier is usually so taken aback by your familiarity with the policies that he accepts the coupon. In most cases, the employee called the manager to the register to get assistance with the transaction.

Here are some of the problems I faced, and how I resolved them:

- Competitor store's coupon: When I presented a "$5 off $25 order" store coupon for a local drugstore from my coupon book, my grocery store's cashier said I couldn't use it because I was not buying a prescription. However, my grocery store's policy is to accept competitors' coupons, and the drugstore coupon did not have any restrictions on the type of merchandise that qualified for the $25 minimum purchase. Because the drugstore sells many of the same items that the grocery store does, they are competitors in my book. I politely explained to the cashier that their store policy is to accept competitor coupons, that this coupon did not specify prescription purchases, and that all she had to do was enter the coupon under their "Competitor Coupon" category. That made sense to her, so she took the $5 coupon off.

- Competitor pharmacy's coupon: In a similar situation, the cashier at my local CVS Pharmacy looked at me blankly when I presented a "get a $20 store gift card with a new prescription" direct-mail coupon from my local Walgreens store. Again, I explained that it is CVS's policy to accept competitors' pharmacy coupons. She processed the coupon and gave me a $20 CVS gift card.

- Coupons that exceed purchase price: This happened to me twice recently. At one store, I had a $20 off coupon for an item that was on sale for $19.99. Because the system rejected the coupon, the teenage cashier handed the coupon back to me and said, "you can save this for next time when the price is higher."

That response made me laugh! I explained that their store would be reimbursed $20 so they would actually profit one penny, and that she should deduct $19.99 as a miscellaneous coupon. She called her manager for assistance and that is exactly what the manager did.

In another instance, I had a $1 coupon for an item I was buying at my local grocery store that was on sale for 99 cents. Again, the system rejected the coupon so the cashier handed the coupon back to me and suggested I save it until the price was higher. The cashier said, "You would be getting the item free if you used that coupon." I said yes, that was the whole idea! He called the manager for assistance and she taught him how to take 99 cents off for each item. Because I had six coupons and was buying six items, that extra step saved me about $6.

Had I not tried to overcome these objections, I would have missed out on $51 of savings in one week. When that amount of money is involved, it's worth being very familiar with your stores' coupon policies. Pay attention to how the experienced cashiers deal with special coupons so that you can easily overcome objections in the future.

Stephanie Nelson shares her savings tips as a regular contributor on ABC News' "Good Morning America." You can find more of her savings tips in her book "The Greatest Secrets of the Coupon Mom" and on her website at www.couponmom.com. She can be reached at shoppingmom@unitedmedia.com.