Will my baby mouse die?!?!?

My mouse has a little bit of fur but his eyes are not open yet, and my mom let me rescue him from the yard after his family was killed by the lawnmower. He started eating finally, but now I'm upset because my mom says I still have to go to school if I can (sigh...). I go to school for 9 hours... and I don't think he'll survive for that long without the heating pad being turned on again (it turns off by itself for some reason) and being fed. Please help? Will he make it through or do I have to miss my school day?