I got this game for my daughter back in 1998. She was 2.5 at that time and I used to play with her on my lap. Before I knew it, she had learned how to use the mouse and she was able to play the game on her own. It was one of her most favorite games, especially the Build-a-Bug section which had a crazy scientist bug who would put together different bug parts to make monster bugs.
The game has three difficulty levels. The first one, it has a voice-over which gives the instructions. Second one, introduces some reading with a voice-over to complement it, and the third level has written instructions only.
I am so glad to see the game is still around. I am debating whether to purchase it for way-in-the-future-possible-grandkids. I strongly recommend this game.