When you're planning a kids' party, one of the key things you'll need for success is to know what not to do. From overestimating kids' abilities to not having enough activities to entertain kids, here are the biggest kid party planning mistakes to avoid the next time to host a celebration for a child's birthday, holiday, or other special occasion.

Misjudging kids' attention spans/abilities.
Do not expect 6-year-olds to sit through a long activity or movie (unless maybe it's Frozen or the Lego Movie) or patiently sit and wait quietly for several minutes doing nothing while a game or food gets set up. Younger children naturally tend to have shorter attention spans, and both younger and older kids will need to work off all that energy from the excitement of being at a party with their friends.

When planning games and activities, make sure they fit to the ages of the majority of the guests. Most younger kids may not be interested in sitting down for a board game like Scrabble or chess, while older kids may become quickly bored by, say, a face painter or balloon twister. Whatever games or fun you set up, try to avoid making them too difficult for younger kids; if you have a mix of different ages (say, at a family reunion or holiday party), tailor the activities so that they work for kids of all ages and various physical and cognitive skills.

Overscheduling
Woe to the parent who envisions a party during which things run smoothly on a tight schedule. Whether it's the birthday boy or girl falling to pieces when things don't go exactly as he or she planned or a party guest who felt that he or she didn't get a fair turn or a bigger piece of cake or is simply tired and cranky, there will be tears, tantrums, and/or a need for a quiet hug and break from the action. Remember this rule of thumb: Where there's a kids' party, there will be a meltdown (or two or three), so plan accordingly. Do not expect all kids to move efficiently from one activity to the next, and allow room for kids to pick and choose which activity they want to participate in.

Planning too many/too few activities.
Like overscheduling, planning too many things for kids to do can be overwhelming and kids will feel rushed. For example, rather than scheduling, say, 8 activities for a 2-hour party, plan a couple of major things (a visit from a costumed character or another entertainer and a game), with food and cake planned around the big entertainment.

But while too many activities are impractical, having too few things to entertain kids can be just as disastrous. Plan on kids spending at least 45 minutes to an hour with a big entertainment activity (musician, clown, costumed character, bounce house, etc.) and have at least one or two extra activities (say, a movie playing in another room or board games set up ready to go) so that kids can find something to do once major activities wind down. (You'll also want something to entertain stragglers who are waiting for their parents to come pick them up after the party.)

Hiring entertainment or services without checking references.
You may have a neighbor or friend who loved a particular entertainer for her child's party. But it's still a good idea to get more references and find out how long that entertainer has been in business. Better yet, hire entertainment or book a venue through an event-service provider such as GigMasters. That way, you not only have access to reliable vendors who have been vetted and whose profiles list reviews and ratings, but you have a third party who can help you with any problems that come up with the booking. Another big mistake that's a close second to hiring someone with only one reference: Paying an entertainer the full amount up front, before the party takes place. Most entertainers will require a deposit, with the balance to be paid upon completion of the party.

Having too few adults/sitters to watch the kids.
Hosting a kids' party will require more hands than you think. Hire a sitter to help you transition the kids from one activity to another or to help out with juice boxes, pizza, and cake and help younger kids to and from the bathroom. You will be so very glad you did.

Thinking you can't afford an entertainer or help.
As mentioned, sitters an be an invaluable asset at a kids' party, but many parents forget to include it in the party budget. Similarly, a lot of parents think that hiring someone to come and entertain the kids will be too expensive. The truth is, a bounce house or an entertainer such as a face painter or costumed character will cost approximately anywhere between $75 and $200 (depending on where you live), and will be well worth the money to have a main event to help entertain kids. For more ideas for things to get for a kids' party, read, "5 Things to Get for a Kids' Party That are Totally Worth the Money."