Places of interest for a toddler 1.5yrs old

Could you please suggest places that could be of interest to toddler of 1.5 yrs
Planning for coming long weekend of 1st Nov.

Where? Tokyo?

Sorry for the miss
Yes Tokyo or Kanagawa or closer to it

Prefer outdoor and if can see some color change it would be perfect!

If your child is anything like mine, simply being able to run around a park and stop to look/touch leaves, pebbles, grass, etc will be of great amusement. It'd also tire them out of course!

Besides parks, there's places like the Anpanman museum at Yokohama, Doraemon museum at Kawasaki, Hanayashiki amusement park Asakusa, Studio Ghibli museum and Ueno Zoo.

there are many standard parks in Tokyo area if your kids still be early to play amusement park and zoo, museum etc.
http://familytravelplan.weebly.com/tokyo-area.html
Regarding autumn color, weekend of 1st Nov is a little early to start it.
Although it is fartur place, you can find autumn color at Yamanashi Shokenkyo as near Tokyo area.
http://www.shosenkyo-kankoukyokai.com/
http://autumnjapan.weebly.com/tokyo-area.html