Get your first 10 from people you know.
You must know parents or know people that know parents.
Do your problem/solution/MVP interviews with these people. Then use them to refer you to others that may have the same issue/be interested.
Pour gas on your social networks - Facebook, twitter, linkedin whatever. Spread the word and force close friends to like/share/retweet etc to maximize reach.
That should get you to your first 50-100 easily.
Beyond that, in parallel, post to /r startups and /r parenting on reddit. Submit link to Betali.st and ProductHunt and do a ShowHN.
With all of this, you should get to your 1000 number.