Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Jumping fun

This jumper is great for times that my son wants to be active but I don't want him crawling all over the house. He laughs and jumps and laughs and jumps. It has a nice simple design (no assembly) and fits a variety of door frames. My only complaint is with adjusting it to the right height. It is difficult to adjust when he is in it and impossible to tell what the correct height is when he's not in it, so getting the right height is trial and error. Over time it has a tendency to slip, so it has to be re-adjusted every so often.