Just 35 miles from Baltimore, there are more than a dozen water rides at Six Flags America (pictured). (Check height restrictions.) A season pass is $64.99, or less if you buy four (sixflags.com/america/attractions/water-park-rides). Or check out the resort-quality but extremely affordable North Arundel Aquatic Center (aacounty.org/RecParks/swimcenters/aquaticcenter), which has two water slides, a splash area and a waterfall. Kids must be potty trained, and two-hour admissions are timed. $4-$8.
Jerry Jackson, Baltimore Sun photo