"Summer School" prep for next year

Well my two oldest are going to be in first grade so I get to figure out free ways to get them ready, any moms from New York state have any tips since part of curriculum is common core?

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NicolePerry, New York
About Nicole
Current: Perry, New York
Birth: May 12
On Moms.com since: Aug 25, 2014
I am a Mommy of two children by birth and one by marriage.