Outings : SUMMERTIME STUFF : Freebies Galore : The county’s no-cost activities may encourage you to be a bit more adventurous. Besides, the price is right.

Sometimes it seems as if everything fun has a price tag, but it’s not true. There are a score of free activities to pursue, everything from Shakespeare in the park and library programs for children to ranger-led hikes.

Not sure if your 7-year-old can sit through a Shakespearean play? Wonder if your visiting friends would find an 1847 adobe of interest? Try it--the price is right and you don’t have anything to lose. No-cost activities may encourage you to be a bit more adventurous.

Special Events

* Point Mugu Air Show: Saturday and Sunday, 8 a.m. to 5 p.m. Everything from the U. S. Navy’s Blue Angels in a sky-high flyover to Budweiser Clydesdales, and with military and civilian performers, a display of old and new aircraft, and food and drink. Located at Point Mugu Naval Air Station on Pacific Coast Highway. Call 984-4715 for information.

* First Sunday in the Park: At Plaza Park, at Thompson Boulevard and Chestnut Street in Ventura, on the first Sunday of every month. A juried arts and crafts fair, with food vendors and roving entertainment. Call 658-4742 for information.

* Concerts in the Park: Sponsored by the Conejo Recreation and Park District, a series of four afternoon concerts at the Conejo Community Center in Thousand Oaks, at Dover and Hendrix avenues. Three Sunday concerts at 3 p.m. are July 21, Boy Howdy, country-Western; Aug. 4, Marlena Shaw, jazz; Aug. 18, Kenny Rankin, soft rock. A Labor Day Monday concert, also at 3 p.m., will feature the Conejo Pops Orchestra. Bring lawn chairs or blankets.

* Films Under the Stars: Bring flashlights, blankets and snacks, and enjoy family entertainment at Mae Boyar Park, 130 Kanan Road, Oak Park. On July 25, “The Jungle Book” (G), 78 minutes; Aug. 22: “Batteries Not Included” (PG), 106 minutes. For information, call (818) 889-7221.

* Shakespeare in the Park: “The Taming of the Shrew” will be offered by the Conejo Recreation and Park District. Call 499-4355 for reservations; tickets are free. The play, staged to intrigue the whole family, is scheduled at 8 p.m. Saturday and 7 p.m. July 21, both times at the Arts Council Cultural Center, 482 Greenmeadow Drive, Thousand Oaks; at 7 p.m. July 13 at Borchard Community Center, 190 Reino Road, Newbury Park, and 7 p.m. July 20 at the Conejo Community Center at Dover and Hendrix avenues, Thousand Oaks.

Places to Visit

* San Buenaventura Mission: 211 E. Main St., Ventura, 643-4318. The gift shop and museum are open from 10 a.m. to 5 p.m. Mondays through Saturdays, and 10 a.m. to 4 p.m. Sundays. A donation of 50 cents for adults and 25 cents for children is requested. The recently restored mission, the last to be completed under the leadership of Father Junipero Serra, was built in 1782. The mission offers a garden, a lovely fountain, an old olive press, as well as religious shrines. A self-guided walking tour booklet is available in the gift shop.

* Olivas Adobe Historic Park: 4200 Olivas Drive, Ventura, 654-4726. Open 10 a.m. to 4 p.m. weekdays, 10 a.m. to 3 p.m. Saturdays and Sundays. Not only a lovely 6.5-acre park with century-old pepper and eucalyptus trees, gardens and grape arbors, the site also has the area’s first two-story home, the original house of Rancho San Miguel. A Chumash Indian thatched hut is among the displays at the visitors center, and some old farm equipment is in the adobe yard.

* Fillmore Historical Museum: 447 Main St., 524-0948. Built in 1887 as the depot for the Southern Pacific railroad. The museum features old tools, dishes, clothing, local Indian artifacts and even old newspapers that visitors can sit down and read. A park across the street is a good spot for a snack or picnic lunch afterward. Open 10 a.m. to 5 p.m. daily.

* Ventura County Museum of History & Art: 100 E. Main St., Ventura, 653-0323. Admission is free Tuesdays. Open 10 a.m. to 5 p.m., closed Mondays. One of the oldest museums in California, built in 1913. The collection includes Indian artifacts, mission and rancho pieces, fine art and, in the Smith Gallery, 197 1/4-life-size historical figures of English royalty and American patriots are on display this summer. Ventura County’s two major industries--agriculture and oil--are showcased in the outside exhibit areas.

* The CEC/Seabee Museum: Channel Islands Boulevard and Ventura Road, Sunkist Street entrance (Gate A), Port Hueneme, 982-5163. Open 8 a.m. to 4:30 p.m. weekdays, 9 a.m. to 4:30 p.m. Saturdays, 12:30 to 4:30 p.m. Sundays. Features a variety of cultural and anthropological artifacts associated with naval engineers. There are toys, money, dolls, costumes, clothing, uniforms and weapons from around the world, a case of Pacific seashells, World War II dioramas, flags, tools and a park with vehicles that the Seabees have used. Bring a picnic.

* Carnegie Cultural Arts Center: 424 S. C St., Oxnard, 984-4649. Open 10 a.m. to 5 p.m. Thursdays through Saturdays and 1 to 5 p.m. Sundays. Formerly the Carnegie Library and Oxnard City Hall, the center was built in 1907 and restored in 1980. This summer, the Oxnard Art Assn.’s summer competition, a judged exhibit featuring traditional to contemporary art from five counties, will be on exhibit. Guided tours are available on request, and a low-cost family art workshop program is also available (call for schedule).

* Channel Islands National Park: Visitors Center, end of Spinnaker Drive, Ventura, 644-8262. Open 8 a.m. to 5:30 p.m. A small marine life museum with an indoor tide pool, displays of Chumash Indian artifacts and a 25-minute film, “Treasure of the Sea,” are featured. A native plant garden and telescopes give a better sense of the local environment, on land and sea. Every Saturday and Sunday at 2 p.m., a ranger leads a special natural and human history lecture at the outdoor amphitheater, and at McGrath State Beach, slide programs are presented by park rangers at 8:30 p.m. Saturdays through Labor Day.

Other Programs

* Libraries: The city and county libraries are running special reading programs for children this summer, including story hours, reading incentive programs, puppet shows and other entertainment. Call your local library for specifics.

* Teen Program: Ojai Recreation Department, Jack Boyd Community Center, 510 Park Road, 646-1872. For eighth- through 10th-graders 1 to 4 p.m. Mondays through Fridays. The program includes supervised games--from Ping-Pong and volleyball to basketball, from billiards to arts and crafts, and will include some day trips to special places. The program is truly free (directors say they have learned that teen-agers won’t participate if it’s not).