Welcome to Frog Forum, Mrs. H. This sounds like an interesting challenge. But it would hold a few challenges.
Right off the bat, I am thinking tree frogs: Red-Eyed tree frog, American Green tree frog, Big Eyed tree frog... If you go with one, stay with one species... It's better for the frog. Tree frogs need vertical tanks, the higher, the better, they like to climb high.
Now one of my concerns would be humidity... Some tree frogs need higher humidity. This could warp the wood. Nor do I think the wood would keep the humidity in. It would also need to be completely secured, as these little buggers are escape artists.
These would be my biggest concerns... But it's possible. How much work are you willing to put into it... ? In order to work, it needs to be ideal for the frogs. After all, we want the wellbeing our the animals, right?
Eric