Do I need ssl?
 

I have a very basic, home-made webpage for students' homework. The host wants to sell me ssl certificates. These must be, I believe, renewed every year.

The kids just fill out a form and click send. There is no sensitive or private data, just a student number and their answers.

I believe ssl is some kind of encryption process.

Do I need an ssl certificate?

You can use free ssl certs. https://letsencrypt.org/

Probably not, and you can get free certificates.

It is difficult for others to say whether you actually need it or not, but I would recommend it for anything that accepts user input. It is both encryption and authentication.

* It identifies the server as being yours and not an imposter
* It guarantees that the data was not tampered with between sender and receiver
* It encrypts each transaction making it unreadable by others in between

You can get free certs - LetsEncrypt.org, I use these and there is nothing second-rate about them. You will need to renew them every ninety days, but there are automated tools to do that for you.

What astrogeek said.
There are also certs available for as little as $10/year with annual or longer renewals.
(Which is not to say there’s anything wrong with the free ones.)

when I shopped for certificates I could get a free one that offered no insurance; if you wanted insurance against losses (it was a commercial enterprise) that's what cost.