HOUSTON -

It is officially summer for many students; and that means parents are looking for things to do that are family-friendly, convenient and low-cost.

We've got a lot that fits that bill in this week's Freebie Friday.

Get some sand between your toes and marvel at masterpieces. Saturday is the 28th annual Galveston Sandcastle Competition Building kicks off at 10 a.mm and goes until 3 p.m. The public votes and awards are at 4:30pm.

It's all happening on East Beach.

Want to stay closer in town? Head over to the GOOF Off block party Saturday. It's short for Garden Oaks and Oak Forest. They'll have a petting zoo, wine tasting and even massages at The Shops at Oak Forest on West 43rd Street and Ella Boulevard from 2 p.m.-6 p.m.

The Houston Humane Society is kicking off its #$100kchallenge Saturday from 10 a.m. until 2 p.m. at 14700 Almeda Road. If it adopts out 1,100 pets by the end of August, the agency could win $100,000. There will be crafts, face painting, a bounce house and mostly importantly, plenty of dogs and cats ready for new homes. Adoption fees will be waived on select pets.

Join the effort to make Houston a more walkable city by hitting the streets Sunday between Studemont Street and Milam Street. From 11 a.m.-3 p.m., roads around Market Square Park will be closed to vehicles so folks can walk, bike, dance and socialize their way down the road.

Find more free and low-cost fun at www.houstononthecheap.com.