Q: Iphone 4 unable to join the network

I've tried everything. I rest the network settings that didnt do anything ... i also unplugged and plugged back in the modem/ router that didnt do anything either. i dont have a password on the wifi either if that matters i can connect to my schools wifi, but not mine at home. my computer and other devices also work with the wifi and they are not having problems so i dont know why my phone wont connect?  it keeps coming up with the unable to connect to the network popup thing  help me please