Events nationwide throughout the U.S.:

First Saturday of every month: Home Depot Kids' Workshops. Free
workshops designed for ages 5-12 (although younger children seem
to be permitted, with parental supervision).  The workshops run from
9:00 am to noon at all Home Depot locations, but it is best to arrive
on the early side, because sometimes stores run out of the project
kits. Kids' Workshops

Various Saturdays each month: Lowe's Kids' Build and Grow Clinics.
Free clinics for kids, but you must pre-register online.  The
workshops run from 10:00 to 11:00 am.  Since reservations are
required, they do not run out of projects, but they won't
accommodate walk-ins. Lowe's Build and Grow Clinics

Saturday mornings: Michael's. Free or cheap workshops are offered
many Saturdays at Michael's, the arts and crafts supply store chain.  
 Michael's

Free museum entry on the first weekend of each month with a Bank
of America account.  For a few years now, Bank of America has
offered to account holders free admission to museums around the
country on the first weekend of each month.  See the link for more
information and locations.http://museums.bankofamerica.com/
Things You Can Do with Your Kids
P.O. Box 267931
Weston, FL 33326
954.864.2314
info@one-beautiful-world.org
Local South Florida Events
Click on the link below for a calendar of usually free kid and family
activities in South Florida:

OBW South Florida Calendar of Events for Kids and Families

Click on the link below for South Florida Parenting's calendar of
events, including a calendar tool that allows you to click on any day
of the month (more comprehensive calendar than the one above,
but the events listed usually are not free):

South Florida Parenting Calendar