Invest in a projector and either a movie screen or erect a sheet, or use the side of your house, and run a movie night. Throw down some blankets and pillows or pop some corn and sit at your patio table and enjoy.
DIY climbing wall My hubby did this for our kids in the backyard. ... Expand Pin Learn ... the-mood-with-outdoor-lighting/pictures/page-10.html?soc=pinterest
Digging a hole and burying your trampoline can make it safer, since it can't tip over, plus it make sit even easier to use. Add water during the warmer months and you've got a unique and fun place to cool off while getting exercise.
Check out the DIY to do this yourself.
Who says all meals have to happen around the dinner table? Toss down a blanket and take it outside to have a picnic on the lawn. If it's raining, you can even do it in the living room on the floor. Push all your furniture out of the way and eat up!
Hit up the dollar store for cheap glow sticks and then fill up soda bottles with water, drop in an activated glow stick, put the lids on tight and set them up like bowling pins. Use something easy like a soccer ball as a bowling ball and get rolling when the sun goes down.
Just because you can't travel anywhere to do something fun, doesn't mean you can't create something fun in your backyard. Whether you have trees or not, you can build an awesome zip line which will make you the envy of all your kids' friends.
Check out the DIY so you can build this more easily and safely.