After a string of educational but underwhelming large exhibits, San Jose’s Tech Museum may have a real hit on its hands with “MythBusters: The Explosive Exhibition,” based on the popular Discovery Channel series.

Nothing blew up during the pre-opening VIP reception at the Tech on Thursday night, though there was a controlled explosion during the press preview earlier in the day. But nobody among the crowd of downtown regulars and Tech Museum supporters noticed the lack of pyrotechnics. There was just too much else going on.

Some people were watching a “reaction time” test where people tried to dodge paintballs on stage and others were seeing whether running or walking in the rain get you wetter. Santa Clara County Supervisor Dave Cortese and Silicon Valley Education Foundation CEO Muhammed Chaudhry raced to see who was quicker changing into a superhero costume in a phone booth.

“This museum exhibit is not your normal museum exhibit,” “MythBusters” co-host Tory Belleci said. “You actually get to be a mythbuster.”

I predict the show — which officially opened Saturday and runs through Jan. 6 — will be a big hit with families, who can do a lot of the hands-on experiments and contests together. That fun do-it-yourself mentality was missing from some of the Tech’s recent big-ticket exhibitions, and it’s no wonder that DIY specialists TechShop is the major sponsor. Tickets are $22 for adults and $12 for kids 17 and under (go to www.thetech.org for details).

The show’s two big names — Adam Savage and Jamie Hyneman — weren’t at the opening festivities, which had to be a little disappointing for the hundreds who shows up. But I heard privately that their appearance fee was too high, and I’m glad the Tech and Team San Jose didn’t spend the extra money in the current economic mood. There was plenty to see and do even without the stars around.

SAY IT WITH FLOWERS: One of the most flowery exhibits this side of Pasadena will be on display Saturday in Santa Clara for the Triton Museum of Art’s third annual Fall Floral Festival.

The event will feature the work of more than 20 floral designers, who will interpret works from the Triton’s permanent collection. Joining professional designers from Bloomster’s, Citti’s Florists and others will be Ikebana designer Kika Shibata and her students, along with Mission College floral design students led by instructor Sandy Lesnewsky.

Admission to the event, which starts at 6:30 p.m., is $50 and includes light hors d’oeuvres provided by four Silicon Valley caterers, plus wine from Joseph George Fine Wines. The arrangements also will be on display next Sunday from 11 a.m. to 5 p.m. for a $5 admission.

COSTUMES FOR A CAUSE: Silicon Valley Cares, which raises funds for Santa Clara County nonprofits, expects a crowd of 500 people at its third annual Broomstick Ball at Dolce Hayes Mansion in San Jose on Saturday.

This year’s beneficiaries are ACCESS, a service of the auxiliary of Good Samaritan Hospital; Almaden Valley Counseling Service;, Hospice of the Valley, and Nike Animal Rescue Effort.

Tickets are $150, and you can get more information at www.siliconvalleycares.org.

SUNDAY FUN: Santa Clara County Supervisor Dave Cortese’s office is again sponsoring the third annual Day on the Bay at Alviso County Park this Sunday. The free festivities, which run from 10 a.m. to 3 p.m., include a barbecue, pumpkins for the kids, kayak rides, bounce houses and a rock climbing wall. You can also get a flu shot, which isn’t really “festive,” but is still a good idea.

Parking and a free shuttle are available at George Mayne Elementary School at 5030 N. First St. More details are available at www.sccgov.org/dayonthebay.

Contact Sal Pizarro at spizarro@mercurynews.com or 408-627-0940. Follow him at Facebook.com/mercurynews.aroundtown and Twitter.com/spizarro.