Wishing to move to CR for 5 months as from August - need infos

For schooling, you will be required to enroll your child in a private school and for 5 months, you will be on a tourist visa, where you will have to exit CR before the time specified on your tourist visa is up, then re-enter for the remaining time of your trip. It is not guaranteed that you will be given the hoped for 90 days.
You may want to consider Monteverde, where I understand they may offer volunteer positions that may include short term schooling for your daughter at a lower fee, but note that most of these 'volunteer positions' are not free.
Another consideration would be Drake's Bay, near Corcovado National Park, considered to be one of worlds 'most ecological places on earth'  but there doesn't seem to be a private school there, and as a tourist your child may not be permitted to enroll a a public school. Since she is of 'kindergarten' age, you could possibly make other private arrangements. Public kindergarten class are only for 2 hours a day and tend to be canceled 'on a whim' and without prior notification.

Hello Adeline and congrats on your first post on the forum of Expat.com

Kindly note that I created a new thread has from your post on the Costa Rica forum to help you get more visibility and interaction.

I invite you to browse through threads in our forum so as to gather some useful infos to get to prepare better your project.

Regards
Kenjee
Expat.com Team

Hola Adeline,

My daughter and I live in a very rural area outside of San Ramon, Alajuela.  You might enjoy this area as there is a lot of wildlife - several varieties of monkeys, peccaries, coatis, toucans, parrots, and many others.  My daughter owns and operates a parrot rescue center here as well - you are welcome to visit if you are interested.  You can see it at https://www.facebook.com/ParrotRescueCenterOfCostaRica  There are also a number of preserves within a few hours of here.

The grade school here is not as strict as it would be in or near cities.  If you are interested in this area, I can ask at the school if they would allow your daughter to attend for the short time period.  Please let me know if you want me to check into it or if you have any questions at all.

There is usually housing available in this area.  The time period you stated is during the rainy season but it's still very nice.  I prefer the rainy season myself.  Housing prices range from $700 per month for a nice cabin up to anything you want to pay.  You can also get Tico style housing for a bit less.

Also, just in case you are not aware, you will need a roundtrip airline ticket - showing your return date in 90 days.  Just make sure you purchase a flexible date ticket so that you can change it later.  When you go through customs, they will ask how long you plan to stay, just tell them 90 days and they will stamp it as such.  Before your 90 days is up you just need to take a bus to Nicaragua or wherever or fly somewhere.  Upon your return the same thing will apply...needing to show your return airline ticket.  Hopefully that makes sense.

Take care,
- Dave