We biked a lot a as a family when the kids were 6 and 8. (and before, with the gator bike along attachment). Like, every weekend and vacation. This means you need a bike carrier for your car to get out to the "neat" places.
Liked seasons pass to the zoo one year, and the science museum another year, especially at 4 yrs to 8 yrs.. If you go 4-6 times it is worth it. I always like science stuff, and the parks at the zoo are very beautiful too. Both on city transit. I had to wait until my daughter was 14 before anyone wanted to even walk through an art museum with me, though.
We would go to a big city park far (1.5 hr) from home, by taking two bikes on the bus with us. That was an adventure, many tourists go there. One or twice per year. Fireworks, etc. The cities will often put on free children's festivals, or small skits, or musicians that are interesting. Even if only a few times per year, it mixes up the outings. Look them up.
My husband likes to build stuff, so showed the kids how to use the wood stapler, scroll saw, etc. and they would make their own bird houses, or "crafts" from wood scraps. while he worked on his projects. Yep, even at 6-8yrs old they can start to use some of the big person tools.
Family board games a big hit at this age. I had to buy some german style games as Monopoly is not my style.
Learning how to take video and post to U Tube is fun too. Stop motion animation anyone? With clay people, now that was fun during winter / rainy season.
We started hiking (instead of biking) at around 10 yrs of age for the youngest, and geo caching is a hit.
There is also a portals game on the cell phone (caution, uses data), that we like to play as we walk around our neighborhood or to new places in town. It is a collaborative on line app game, that you attack other people's portals, and defend your territory. Kids really love it.
Check out family "meet up" invites and see if there is anything interesting! We ended up forestry (free) camping while the kids built rafts in the woods one year after getting to know a few other families.