My happiest memory in childhood

My happiest childhood memory is that when I was young,I used to spend weekends with my parents flying kites.Usually,we would fly kites in a park near my home,which is beautiful with a path winding along the lake.After that,we would often find a restaurant to have some delicious food.It is my happiest memory because I spent that time with my parents,which I am unable to do now since I live in the university far away from my home.Therefore,that's the best memory of my childhood.

you can say "we would fly kites" or "we flew kites"

That's a wonderful memory! When I was a child I used to fly kites with my parents, too. :-)