Within 5 miles of me with 2 adults and 2 kids and $100, you could go to a trampoline park, ropes course, bowling, hours at an arcade, water park, race go-karts, several months of pool membership, or 5+ museums. Possibly 2 of those activities.
For free there’s dozens of playgrounds, courts and fields for any sport, community and religious-sponsored events, and after you can get a nice sit down meal with money leftover from your $100 budget.
$100 would be above many families entire entertainment budget for a week.