For teachers: family messaging that does not require you to be two people
Nobody consulted you about this purchase and you will use it more than anyone who did. This page covers the three things that determine whether a communications platform is tolerable in a teaching week: how many accounts you need, when it can reach you, and whether your families are asked to pay for anything.
| Action | Teacher can | Where it stops | What the log records |
|---|---|---|---|
| Message the guardians of your own students | Yes | Selecting a student expands to that student's guardians only | Author, recipients, channel, time, delivery outcome |
| See another classroom's families | No | Isolation is enforced in the database, not by hiding a menu item | Nothing to record — the query returns zero rows |
| See another school's or district's data | No | Hierarchy-aware row-level security; with no organisation context set, queries return nothing rather than everything | — |
| Send at 22:00 | Composed, not delivered | Quiet hours default 21:00–07:00 and are applied at dispatch, so the message waits | Composed time and dispatch time as separate facts |
| Bypass quiet hours | No | Only an emergency-flagged send bypasses, and that is gated on a capability teachers do not hold | Who flagged it, if anyone did |
| Check a translation before it sends | Yes | Preview renders in the composer; there is no glossary and no "see original" footer on the delivered message | Target language, so analytics stay honest |
| Send a test to yourself first | Yes | Delivered only to you, prefixed [TEST], on the real channel | Recorded as a test, not as a send to families |
| Post as a group identity | If you administer the group | Group admin is separate from district admin | The true author's person ID, always, even on group posts |
| Attach a photo or a PDF | No | No attachments, no photo or video sharing, no upload path exists | — |
The second-account problem
A meaningful proportion of any staff room parents in the same district they teach in. In most family communication platforms that person ends up with two accounts: a staff login and a parent login, usually on different email addresses, definitely with different notification preferences, and reliably with one of the two phone numbers out of date. Then a message goes to the parent account about their own child's class and it lands in the account they never check.
Kastr models a person once. One person row, many role rows, each with a start date and an optional end date. You are genuinely a teacher and genuinely a guardian at the same time, with one phone number, one language preference and one set of consent states. When you move from third grade to the middle school in August, the old role ends and the new one begins without erasing the fact that the old one existed — which matters the first time somebody asks who was teaching a class in March.
This is not a common design. In our own competitor matrix the single-identity row reads "nobody".
Quiet hours, and the boundary they actually enforce
Quiet hours default to 21:00 to 07:00 and are applied at dispatch rather than at composition. The practical effect is that you can write a message at 22:15 on a Sunday because that is when you have time, and it will not arrive on ninety phones at 22:15 on a Sunday. It goes out at 07:00.
Only an emergency-flagged send bypasses quiet hours and per-family channel preferences, and the emergency flag is gated on a capability that a classroom teacher account does not hold. That is deliberate: the value of an emergency channel is entirely a function of how rarely it is used.
The boundary that runs the other way — families reaching you — is a policy question your district sets, not a product one, and you should ask about it before rollout rather than after.
Translation you can read before you send it
The composer renders your draft in other languages, through DeepL, before anyone receives it. The reason this matters to a teacher specifically: the sentences you send home are full of terms that machine translation handles badly. "Retention", "referral", "conference", "credit recovery" and "behaviour plan" all have an education meaning and a general meaning, and a general model does not reliably pick the education one. Reading the Spanish version before it goes out takes fifteen seconds and prevents the conversation you would otherwise have on Tuesday morning.
Two limits, stated plainly. DeepL supports around 30 target languages — not the 47 that circulates in this market, including on our own site historically — so some of your families are not covered by any machine translation worth using. And there is no district glossary, so you cannot pin a programme name or an acronym to a fixed translation. If a term matters, write around it in the English source.
What this is not, so you can plan around it
No attachments, no photos, no video. There is no upload path anywhere in the product. If your classroom practice is built on sharing photos of student work, this platform does not replace that and we are not going to imply it does.
No push notifications. Kastr sends SMS, email and voice. There is no mobile app and no device-token registration, so there is nothing to push to.
No AI drafting. Nothing writes your message for you.
No class or grade targeting. Audiences resolve as explicit person lists or everyone. You select students; you do not select "period 4".
What you do get in exchange is narrower and, we would argue, more useful to you: an account that does not multiply, a cost figure that appears in the composer so a district never quietly bills your building for a voice blast, and product releases timed to the calendar — major changes land in May with professional development material, and September through May is polish only. Nobody else in this category commits to that, and every teacher who has had a platform's interface redesigned in late October knows why it matters.
What your families are and are not asked for
Contract clause §9.4 prohibits us from marketing to district families, selling to them, or taking any family-facing subscription revenue — permanently, and regardless of who owns the company. There is no premium tier for parents, no upsell inside the family view, and no advertising.
This is the clause that distinguishes a district-funded tool from a consumer app that districts happen to use. If you have worked in a building where the free classroom app started charging parents for features that used to be included, you already understand what the clause is for. Clause §11.2 backs it: if Kastr is acquired or materially changes its data terms, the district can terminate within 90 days with a full export and a prorated refund.
Questions people actually ask
Do I need a separate account if my own child attends this district?
No. One person record carries multiple effective-dated roles, so you are a teacher and a guardian on the same identity, with one phone number and one set of preferences. This is unusual in the category — most platforms create a record per role and the two drift apart.
Will parents be able to reach me at 10pm?
Whether families can message you at all is a district policy decision. What the platform enforces is the other direction: quiet hours of 21:00–07:00 by default, applied when messages are dispatched rather than when they are written, and bypassable only by an emergency-flagged send that requires a capability teacher accounts do not have.
Can I check the Spanish version before it goes out?
Yes. The composer renders the draft in other languages via DeepL before sending, and you can also send a test to yourself, prefixed [TEST], on the real channel. There is no district glossary to pin terminology and no 'see original' footer on the delivered message, so if a translated term looks wrong the fix is to change the English.
Do families have to pay for anything?
No, and it is contractual rather than a promise. Clause §9.4 forbids family-facing subscription revenue, marketing to families and selling to families, permanently. Clause §11.2 gives the district a 90-day exit with export and prorated refund if we are acquired or change our data terms, which is what prevents a new owner from undoing §9.4.
Can I send a photo of the class project home?
No. There are no attachments and no photo or video sharing — no upload path exists in the product at all. That is a genuine gap against tools teachers use daily, and it is on this page rather than in a demo because you would find it in your first week.
One price. Every feature. Locked for three years.
$3.50 per student per year under 5,000 students. No tiers, no add-on modules, no per-message fees. Published on the site because you should not have to book a call to learn a price.