Soap Box Derby

The 13th annual All-American Rhode Island Soap Box Derby is today beginning at 9 a.m. on Memorial Boulevard near Easton’s Beach in Newport. The event, sponsored by the Newport Lions Club, is open to boys and girls ages 8 to 17. The winner will represent Rhode Island in the national championship in Akron, Ohio, on July 26. A bonus: There’s a carnival in the beach parking lot, noon to 6 p.m. today and tomorrow. For more information, go to www.newportlionsclub.com.

Open doors to history

As part of National Preservation Month, the Preserve Rhode Island organization presents “Thresholds…Step Inside History,” an open house of two dozen historic sites around the state. Admission is free; hours are noon to 3 p.m. For a list of sites, go to www.preserveri.org.

A family fair

The 18th annual Burrillville Family Fair is today, 10 a.m. to 2 p.m., in the Town Common off Main Street in the village of Harrisville. There will be a parade, live entertainment and information booths. In case of rain, the event will take place in the Burrillville Middle School. For more information, call (401) 568-9470 or visit www.burrillville.org.

Just for Mom

Casey Farm in Saunderstown presents its annual Mother’s Day weekend sale of plants: organic vegetables, herbs and flowers. There will also be children’s activities and tours of the 18th-century house museum.The event is today, 8 a.m. to 4 p.m., and tomorrow, 8 a.m. to 2 p.m. Admission to the museum is $4. The farm is located at 2325 Boston Neck Rd. For more information, call (401) 295-1030 or visit www.caseyfarm.org.

You’ll find more greenery at URI’s East Farm Spring Festival. From 10 a.m. to 2 p.m. today, the College of Environment and Life Sciences and its Master Gardeners program present horticultural activities and exhibits, and an array of plants for sale. East Farm is located on Route 108 in Kingston. For more information, call (401) 874-2900.

In honor of Mother’s Day, Roger Williams Park Zoo admits mothers (including grand- step- and honorary) for half price tomorrow. The first 150 mothers to enter will receive a complimentary rose, and all may enter a raffle for a $100 gift certificate. There’ll be presentations by the Rhode Island Orchid Society and the Rhode Island Rose Society. The zoo is located at 1000 Elmwood Ave., Providence. Regular admission is $12, $8 for seniors, $6 for children, 3-12, and free for those younger. Call (401) 785-3510 or go to www.rogerwilliamsparkzoo.org.