You can use photos from digitalfreephotos.com for your website or blogg but you must provide a link to digitalfreephotos.com.
You can use photos from this website on you school project but you have to refere that you took the foto from digitalfreephotos.com
Do you have other questions concerning how you can and can not use photos on digitalfreephotos.com. Send me an email, info[@]digitalfreephotos.com
Example of refering to digitalfreephotos.com