Question: 1. if you create an instance variable in a class, is the default value true or false until otherwise changed?
2. Is it good practice to have an instance variable as ex. true then change the value to false and use that variable throughout your class? Or is that something you should conceptually avoid in terms of using instance variables?

Answer: 
> 
> if you create an instance variable in a class, is the default value
>  true or false until otherwise changed?
> 
> 
> 

If the variable is type of boolean, then default value is false, primitives variables default value id `0`, object variable/reference variable default value is `null`

> 
> Is it good practice to have an instance variable as ex. true then
>  change the value to false and use that variable throughout your class?
> 
> 
> 

You can do this, it's depends on your requirement.
> 
> if you create an instance variable in a class, is the default value true or false until otherwise changed?
> 
> 
> 

If the member is primitive , then `false`. If it is a wrapper, then `null`

> 
> Is it good practice to have an instance variable as ex. true then change the value to false and use that variable throughout your class? Or is that something you should conceptually avoid in terms of using instance variables?
> 
> 
> 

Setting true or false will be depends on your class context. No issues with it at all.

For ex: You are creating an customer Object and having an instance memeber isActive. If your design allows that all customers by default active then yo are right.