This is not a comprehensive list of locations or activities, it is just a place to start in planning your daylongs.

Cataract Falls from Rock Springs go down, or from Alpine Lake and go up

Huge park/Inspiration point great views of the Bay and Mt Diablo, San Pablo Dam

Can park at Roberts or park off road and walk around that area and make forts or find forts already built

Includes stop at Girls Camp. Was originally trying to reach Redwood Valley Railway but we ran out of time and energy.

https://www.google.com/maps/dir/Skyline+Gate+Staging+Area,+8490+Skyline+Blvd,+Oakland,+CA+94611/37.8260495,-122.1759462/37.8372454,-122.1824798/37.8453016,-122.1934026/Sibley+Backpack+Camp/37.8507723,-122.1898044/37.8565374,-122.197876/37.8563496,-122.2066804/37.8599845,-122.2124071/37.8673395,-122.2165837/@37.8272772,-122.1798213,14.05z/data=!4m22!4m21!1m5!1m1!1s0x808f87e59b31d7d9:0xbaed87c45ceebd09!2m2!1d-122.1853764!2d37.8317039!1m0!1m0!1m0!1m5!1m1!1s0x80857d42af529f1b:0x8dcb3c8062ab2526!2m2!1d-122.1969473!2d37.8503318!1m0!1m0!1m0!1m0!1m0!3e2

Stops at Girls Camp, Redwood Peak and Redwood Bowl for games and circling. 5.4 mile hike, 2.25 hours of walking and plenty of time for rest breaks and activities

https://www.google.com/maps/dir/37.8212317,-122.1746458/Skyline+Gate+Staging+Area,+8490+Skyline+Blvd,+Oakland,+CA+94611/37.8160087,-122.1741483/37.8178426,-122.1766146/Moon+Gate/37.8264382,-122.182874/37.8314477,-122.1853819/@37.8234251,-122.1842937,15.82z/data=!4m19!4m18!1m0!1m5!1m1!1s0x808f87e59b31d7d9:0xbaed87c45ceebd09!2m2!1d-122.1853764!2d37.8317039!1m0!1m0!1m5!1m1!1s0x808f87c325cd7df3:0xc7dda4c1f9572414!2m2!1d-122.1867922!2d37.8216846!1m0!1m0!3e2

walk Lake + go out on boats > get ice cream or food

Lots of cool graffiti and random structures/good exploring/close to Berkeley

have dinner > go to Chabot for late night space viewing + full moon night

Great for Spring Wildflowers/hot in Fall/Summer no coverage/Shade

Under-appreciated extra option for hikes out East. Lots of trail varitions. BEAR CREEK STAGING AREA HAS CONFUSING NAMESAKE NEARBY, be careful

https://www.google.com/maps/dir/Bear+Creek+Staging+Area,+16+Bear+Creek+Rd,+Lafayette,+CA+94549/37.9470386,-122.1632671/37.932017,-122.1333892/37.9272505,-122.1514705/37.9274864,-122.1560281/@37.9355372,-122.1541924,14z/data=!4m12!4m11!1m5!1m1!1s0x8085635818004aef:0x6d1f0e6c2b3de80d!2m2!1d-122.1577817!2d37.927057!1m0!1m0!1m0!1m0!3e2

unfortunately there is a very frustratingly named East Bay Municipal Utility District "Bear Creek Staging Area" just before the turn off on the right to the Briones Regional Park "Bear Creek Staging Area"! As a map maker... I'm a little furious! Bad naming conventions :(

2,789 acres along the Wildcat Creek watershed and the surrounding hills and ridges. The park extends from the Tilden Nature Area above the Berkeley hills in the south to historic Alvarado Park at the north end in Richmond.

https://www.ebparks.org/parks/wildcat/

Small(ish) park in Berkeley, fields, trails, playground

https://www.cityofberkeley.info/Parks_Rec_Waterfront/Trees_Parks/Parks__Cordornices_Park.aspx

Can get to the top of Mt Tam from there with ambitious enough group

https://www.google.com/maps/dir/Pantoll+Campground/37.9053715,-122.603555/37.9085427,-122.6072534/Rock+Spring+Trailhead/37.9195566,-122.6152085/Potrero+Meadows+Trail,+California+94970/Mt+Tamalpais+view+point,+California/37.9181205,-122.5811817/Pantoll+Campground/@37.9156219,-122.6034954,15.12z/data=!4m56!4m55!1m5!1m1!1s0x808591a06a1c71f1:0x413d9f55ac13ff27!2m2!1d-122.6038858!2d37.9039927!1m0!1m5!3m4!1m2!1d-122.6109256!2d37.9105927!3s0x8085917184ea02fd:0xd215a8493bd92ea8!1m5!1m1!1s0x80859171bbdb688b:0x5672a7f0e8440151!2m2!1d-122.6126681!2d37.910698!1m0!1m20!1m1!1s0x8085914165d57657:0xffee741daebf4f54!2m2!1d-122.610316!2d37.9257579!3m4!1m2!1d-122.6072044!2d37.9262985!3s0x8085914102259315:0x4926c6b93e99c464!3m4!1m2!1d-122.5842807!2d37.9320292!3s0x808591200e8f494d:0x195c17948a479107!3m4!1m2!1d-122.5767039!2d37.9282977!3s0x808590e15a7a6dd9:0x91a8326d534b19d5!1m5!1m1!1s0x808590e186d28739:0x9a1498bd96335b88!2m2!1d-122.5800712!2d37.9273202!1m0!1m5!1m1!1s0x808591a06a1c71f1:0x413d9f55ac13ff27!2m2!1d-122.6038858!2d37.9039927!3e2

swim spot off trail, can also hike to resevoir and loop back down to parking area (official trail)

cleaner when it's higher water (not late summer)

Hike to the beach/can be busy on the weekends. (Can do a longer hike from Tennesse valley to Muir Beach - possibly have a car on either end)

Hike to Lake and then can swim there/can be busy on the weekends

2.6 miles of hilly hiking, between two beach locations. Could bring swim-wear. Lots of sandy beach fun. Extra side hikes also available

https://www.google.com/maps/dir/Headlands+Lookout,+Sausalito,+CA+94965/Black+Sands+Beach/37.8288894,-122.5140081/37.8295023,-122.5244926/37.830171,-122.5286961/Rodeo+Beach/37.8317714,-122.5361202/@37.8261284,-122.5279457,15.18z/data=!4m24!4m23!1m5!1m1!1s0x808585dcf6a552cd:0x8a0e8dbe389c9cd1!2m2!1d-122.510798!2d37.8275312!1m5!1m1!1s0x808585deb406cdbf:0x7e0d2308534ebee3!2m2!1d-122.5086904!2d37.8243305!1m0!1m0!1m0!1m5!1m1!1s0x808585f55ba76df9:0xa205da79abffc9a1!2m2!1d-122.5370428!2d37.830669!1m0!3e2

Fort Chronkite or Rodeo Beach - clean up competition for fullest bag > nature time in Headlands w view of SF

farther down at other bridge is another swim spot, where Sir Francis Drake hits - less visited swim spot, second bridge on left under bridge @ salmon crossing

Awesome. Hardly any people, pond at the top (you can swim in), hill climb to the top then pretty flat or drive all the way up.

https://www.marinij.com/2014/01/19/hike-of-the-week-mount-vision-offers-grand-views-of-drakes-bay/

https://www.nps.gov/pore/planyourvisit/beaches.htm

Professional ropes course (book well in advance, good for later in the group, will be additional cost to families).

https://goo.gl/maps/NsSiLmcDsh1nwzca6

Nice large park, walking, flat, playground, boat rentals