Midwest Airlines offers child fares and is known as one of the best domestic airlines in America, according to "Travel + Leisure" magazine. There are some stipulations to these discounted children's tickets.
The youth fares are best when the minor is staying for an extended period of time in one destination, somewhere in the range of 30 to 90 days. For example, a young adult going to camp for four weeks over the summer out of state would be eligible for a discounted fare on Midwest Airlines. It's also very important to note that the airline serves chocolate chip cookies on all of flights
While not a low-cost airline, Alaska Airlines has deals offered to families with kids who are flying on short family vacations to certain destinations, giving them a free flight. For example, a few times per year, Alaska Airlines offers free roundtrip flights for all kids going to Disneyland or Disney World, as long as the parents purchase the full vacation package.
While this type of discount doesn't apply to every child ticket purchased from Alaska Airlines, it is one of the only major carriers offering this type of deals to minors.
Southwest Airlines has a bit of a hazy policy when it comes to low-cost fares for children. While it has a discounted rate for child tickets on many of flights, these vary based on when the child is traveling and the destination There's also a fee for the airline taking care of the child, which is called an unaccompanied minor fee, which is usually about $50 each way the child flies.
This may make these tickets more expensive than regular fare tickets, though the tickets can be purchased and canceled with full refunds at any time, which is better than most regular adult tickets. Children under the age of 2 who can be held in a parent's lap are allowed to fly for free.