Two school desks. Fully adjustable. 1 for $25 or 2 for $40.
Can fit small kids and big kids. Lots of adjustment settings with the legs.
The tops do not lift up. Instead you put stuff in the space underneath the desktop. No moving parts means they will last forever.
Lots of huge desks that are not adjustable are for sale on Craigslist. These are right sized for kids, lightweight, fully adjustable, and you can put them in any room quickly and easily. Fits in a kitchen, living room, bedroom, and even in some people's bathrooms.
My kids got 10 years use out of these and they were very well taken care of. They look new.