Power button doesn't work

Hi, my MacBook does work absolutly fine when it’s turned on, execpt the power button. The button don’t react on any action.

I can’t do an SMC reset or anything else. To start the MacBook I have to open the buttom side an disconnect the battery. After reconnect the battery I plug in the magsafe adapter and the MacBook boots automaticly.

Is there another way or workaround. My daughter uses the MacBook sometimes for school and I don’t want her to open the MacBook.

Please excuse my bad english.