Many times when our daughters were younger, they would go on activities, especially with our church. On those activities it was often necessary to eat at a fast food restaurant. This can get very expensive and some weeks we just didn't have the money for them to go and eat. We quickly found out, though, that many places to eat, especially McDonald's, have a $1 menu. They could get a dollar burger, dollar fry, and get ice water to drink. Now we will often do the same thing when we are on the road traveling. Saves quite a bit of money.
I have only one caveat about ordering from the dollar menu - make sure you actually look at the menu, even if you've been to that restaurant many times. At the McDonald's where I live they have taken most things of any value off their dollar menu. Boy, am I glad I looked at the menu before I ordered the last time!
Check with your local McDonald's and Wendy's around each holiday (or season). I know Wendy's here in Kansas City offers the Jr. Frosty coupons (10 for a $1, I think) for Halloween and McDonald's offers the coupons around Halloween, then Christmas, Valentines Day, and maybe other times.
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I'm doing a research paper right now in English on how dollar menus are very important to our society and how every fast food should have one.