The short answer
Yes, and it should be bookable online rather than arranged by message. A trial class booked from the website, then term enrolment, with the flow explained on the page.
Asking a first-time parent to commit a term fee to a room she has never been in, full of people she has never met, at a time of life when she is not sure she can reliably leave the house, is a big ask. The trial is how you make it a small one.
Charge for it
A free taster fills the hall with people who do not come back, and it tells the parent the class is worth nothing.
Price the trial at roughly the per-class rate of a term block. That is enough to mean something and small enough not to be a decision. Whether the trial fee comes off the term price if she enrols is your call, but say which on the page either way.
Book it online, not by message
This is the whole point. Trials arranged one at a time through Instagram messages are the largest hidden cost in a baby class business: every one is a conversation, a manual note on a register and a payment you chase.
ClassForKids, Bookeo, TeamUp and Sawyer all handle a single trial session against a term as a block. Set the trial up as a session type that takes one space in a named week, so the register is right and the room is not oversold.
Say what happens next, before she books
The commonest reason a parent hesitates over a trial is not the money, it is not knowing what she is agreeing to. Four lines on the class page settle it.
What the trial costs and whether it comes off the term. That booking a trial does not enrol her in anything. That if she likes it she can join the current term from that week, paying pro rata for the sessions left. And when the next term starts if the current one is nearly done.
Put the reassurance next to the button
The parent booking a trial is nervous about the room, not the class. Next to the Book a trial button, link the first-class page covering parking, buggies, feeding, what to bring and what happens if the baby cries.
That link converts better than any amount of copy about the benefits of sensory play, because the objection it answers is the real one.
The follow-up decides everything
Trial to term is the number the business runs on, and it is won in the two days after the class.
Set an automated message for the day after every trial with one link that enrols her in the remaining sessions of the term. One link, one decision, no arithmetic. Add a single line about the next term for anyone joining too late to make the current one worthwhile.
If your platform cannot automate that, do it by hand the same evening. It is the highest-value twenty minutes in the week.
When a trial is the wrong offer
Two cases. A short fixed course, such as a five-week baby massage block or a weaning workshop, does not have a trial, because week one is the foundation of it and dropping into week three makes no sense. Say so plainly and offer a conversation instead.
And a class that is full does not offer a trial. It offers the waitlist, which should appear in place of the Book button rather than the page simply looking broken.
What to do about the free-taster competitor
If a national brand nearby runs free tasters, do not match it. Compete on the things a parent can see before booking: the age bands explained, the price stated, the venue and parking answered, the leader named with her training shown, and reviews from local parents.
A parent choosing a class for a twelve-week-old is choosing on reassurance, not on a saved ten pounds.
Make it findable
The trial is the offer, so it belongs where people are. In the header on every page. On every class page, deep linked to that class. Under the price table. On the first-class page. In your Instagram bio link, tested inside the Instagram in-app browser where payment sheets most often fail.
Then track trial booking clicks by page, so you know which page is doing the persuading and which one is being read and abandoned.
Where this sits
Trial booking that converts to term enrolment, with the flow explained in plain words and the practical worries answered next to the button, is the core of every baby class website we build, and the same small-first-step pattern runs through our wider childcare and family websites. The packages are on pricing. Sell the one class. The term sells itself in the room.