Hey Katie, I would imagine that most people, besides being motivated by the thought of having someone whom they can trust who is an adult to care for their kids (a huge relief to them and hence their enthusiasm I ‘m guessing), also probably know you are Canadian and that you can’t work a regular job, and probably just like You and want to see you do well at whatever you are doing. People are also especially interested in young couples starting out I think, and want to support them.
If you announced that you were taking in sewing you’d probably be similarly swamped simply because people like to help each other out by giving each other business.
Despite your age,  I doubt that they consider you to be a typical teenager type babysitter, you are obviously a married woman and that accords a different level of commitment and experience on your part, and also increases the likelihood and expectation that they consider you a peer. 
Being as there is little availability of quality sitters, from what you say, I would imagine that they would be both grateful to you for the help, and utterly thrilled to come pick you up if it means they get Sister M.  for their kids!
I imagine N&D having someone like you available to them in Leth. for example and how thrilled they would be! 
Another thing is that each person thinks that they are the only one asking you and don’t realize that every Tom Dick and Emma already has.  /images/smileys/icon_smile.gif So, my first advice is Try not to be annoyed , people aren’t trying to impose on you, they are seeking to hire you for a mutually beneficial situation.
For letting them down gently…

I think its important to Thank people for their interest in you first, say something nice about them, and then indicate you are unable to do it, and leave the door open if you think you might be interested at some point in the future (like if you got a car, want to raise a little extra cash for a project etc).  For eg;

“Thank-you so much for thinking of me, you have such cute little kids, I’d love to help you out, but I’m afraid my schedule is full right now.  Would you like me to keep you in mind if I have an opening?”
I’d also hear people out on what they are wanting.  It may turn out that they needed you for one morning only on a one shot deal, and that might work for you that week where it would not have on another week, or you may have a month where you need or want a little extra cash and are wiling to alter your schedule to earn it. 
The trick is to let the word get out that you are pretty booked, and hard to get time with [cuz you are SO GOOD, of course!:) ] and never to feel obligated to commit on the spot.  Ask them to call or email you the particulars, and don’t answer right then.  That way you always have time to consider whether it will work for you without the pressure of someone standing waiting for an answer, and you can always say ’ I’ll check my calendar and get back to you’ or ‘let me review our commitments and I’ll call you tomorrow’ etc. 
Last thing is you might consider is charging a higher rate and having more requirements for a weekend- it will limit the number of people who can afford you, and if you do choose to accept a job you won’t resent giving up your time if you will be getting paid extremely well for it. 
Hope that helps!

I totally feel for you sweetie, bless your heart for being there and caring about all those kids and families in your ward – it’s obvious that they see you have an incredible love for children and that’s why they want YOU. As a parent, it’s hard to find someone who you want your little ones to be with when they can’t be with you. I can hardly blame them all for wanting THE BEST! /images/smileys/icon_smile.gif
I had a cousin in a similar situation, and she refused to call it “baby-sitting” and instead decided that she would “Tend” their children which made it feel to her more grownup and like a job. It’s amazing how the smallest things can help get us through.
I know that if you feel put on the spot it’s hard to say no, you feel horrible when you know that you just don’t feel like doing something on a weekend, but you also don’t want to let someone down. I used to say that saying no to babysitting is just like saying no to peer pressure, plan your “out” ahead of time so that it’s not flustering to you. I loved what Mom said about getting back to them, I’d likely say “Oh thank you so much, I think your kids are so cute. I’ve been very booked lately so I’ll have to get back to you. Thanks for thinking of me.” Then when you evaluate whether it right, all it takes is a simple “I checked and this weekend isn’t an option for me. “
Katie, I really admire your love for your ward family and your desire to tend those children. You have a loving heart and I’m sure that’s why everyone is taking notice now. Just remember to value yourself, and your time with Conor too – everything needs balance and I have no doubt that you can both serve and honor yourself as well.
Go get em’ Tiger!! LOL!! (I always wanted to say that)

raise your rates, that way it’ll weed out the cheap ones and then if you are doing it at least your making a wack of cash! good luck! sucky problem, “babysitting” can bring about so many awkward moments.

Thanks for the advice. Inhale exhale. It’s hard to be popular. I guess I am a great resource and people are just trying to get some! Ha. I’ve thought about it and I would way prefer an adult babysit than a 12 year old. I’ve heard a few babysitting horror stories!!

okay,that looked MUCH shorter when I typed it!

I totally agree with Catherine, she had some very good points.  You could have a weekend rate and a week day rate. That might encourage people to re-work their schedule to book you during the week when it is more convenient for you. You could even formally announce you are starting a homebased business and call it “Katie’s Instant Knannie Service”. And yes, i know knannie isn’t spelled with a “k”, but it is kind of kfunny! LOL.

I think everyone’s ideas are really great! You could also say something about how you’re busy but maybe another time, and you know someone else who might be able to do it (me). Give them my home phone number (you don’t have it I don’t think… you just have my cellular) if you really want to spend that night at home! I don’t mind… and if I just can’t do it I don’t really have a problem with telling them “no.”
But really, if you need a break from tending, or whatever else… don’t ever feel bad about saying no! People understand that you need your life, too–and that your life isn’t tending their kids. You are not at their disposal. You are an adult, married woman who has a life just like them.

Do you ever ask them if you can have your husband over while you are tending? That’ll remind them that you are an adult!
Personally I think it is an easy way to make some decent dough…and the more frequently you watch the same kids the easier it should get. I’d try and go exclusive with some families that can afford you and go out often. Weed out the ones you don’t want and tell the ones you do want how often you are able to tend.
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