PV Gap

Thelma Said:

How much would cost to put solar panels on an average size house?

We Answered:

If you are asking about solar electric, then the amount of electricity you use and if you have a good south facing roof for mounting them tends to matter more than the size of the house.

My guess is that you are just wondering if it is a good idea.
Well, it looks like about $11,000 for 1300watts for a grid tie system.
That's 1300watts on the perfect day.
From a payback stand point it still tends to take 12-20years for the system to pay for its self depending on your electricity cost and location.

Solar to heat is more efficient so solar hot water heat has a better payback.

Sandra Said:

How much would it cost to install solar panels at my high school?

We Answered:

Depends on how much area they have to work with, how much subsidy they might get for the installation from the power company and other possible sources like The Department of Energy.

As a ball park figure, estmate between 650,000.00 dollars (US) and 1.2 Million for a typically sized US high school.

A lot depends on that potential subsidy because it could potentially cover the installation costs. Another factor is if the roofs are strong enough to support the weight of the system.