На полдник бабушка дала детям по одной ватрушке.

На полдник means for an afternoon snack or as an afternoon snack.

In Russian, на is often used with meals or eating occasions:

• на завтрак — for breakfast
• на обед — for lunch
• на ужин — for dinner
• на полдник — for an afternoon snack

So this is a very normal Russian pattern: дать что-то на полдник = to give something for the afternoon snack.

Here полдник is in the accusative, but since it is an inanimate masculine noun, its accusative form is the same as the nominative: полдник.

Полдник is a light meal or snack eaten in the afternoon, especially in traditional family or school contexts.

It does not map perfectly onto a single English word, but common translations are:

• afternoon snack
• mid-afternoon snack
• sometimes just snack

So на полдник suggests not just random eating, but food intended for that particular snack time.

Дала is the past tense feminine singular form of дать (to give).

Why feminine? Because the subject is бабушка, which is grammatically feminine.

Compare:

• бабушка дала — grandmother gave
• дедушка дал — grandfather gave
• они дали — they gave

Why дала and not давала?

• дать / дала is perfective: it presents the action as completed, a single whole event.
• давать / давала is imperfective: it would focus more on process, repetition, or habitual action.

So бабушка дала детям... means she gave them the pastries as a completed act.

Because детям is the indirect object: it tells us to whom the grandmother gave something.

With дать (to give), Russian usually works like this:

• giver = nominative subject
• thing given = direct object
• recipient = dative

So:

• бабушка — subject, nominative
• дала — gave
• детям — to the children, dative
• по одной ватрушке — one vatrushka each

The dictionary form is дети (children), and the dative plural is детям.

It means one vatrushka each.

This is a very common Russian distributive pattern:

• по одному яблоку — one apple each
• по две книги — two books each
• по чашке чая — a cup of tea each

So in your sentence, the idea is not that there was only one pastry total. It means each child got one.

That little word по is doing a lot of work here: it signals distribution across the group.

Because after по in this distributive meaning, Russian normally uses a different case pattern from the ordinary direct object.

If you said:

• бабушка дала детям одну ватрушку

that would usually mean Grandmother gave the children one vatrushka — likely one pastry total, to the children as a group, or the sentence would be ambiguous.

But:

• бабушка дала детям по одной ватрушке

clearly means Grandmother gave the children one vatrushka each.

Here both words are in the dative singular:

• одной — dative singular feminine of одна
• ватрушке — dative singular of ватрушка

This is the normal form after по with one each.

Because the phrase is built around the idea one per person.

Russian treats this as a distributive unit:

• each child received one vatrushka

So the noun stays singular inside that little phrase:

• по одной ватрушке — one vatrushka each

Even though in real life there were multiple pastries, Russian is describing the amount per child, not the total number.

This is very natural in both Russian and English:

• They got one cookie each
• not necessarily they got cookies each

A ватрушка is a traditional Russian pastry, usually a round bun with an open center filled with творог (farmer’s cheese / curd cheese), though other fillings can exist.

For learners, it is often easiest to think of it as a specific Russian baked good rather than trying to force an exact English equivalent.

So in translation, you might see:

• vatrushka (transliterated)
• cheese pastry
• cheese bun

Depending on how literal or natural the translation is meant to be.

The sentence is:

На полдник бабушка дала детям по одной ватрушке.

A natural breakdown is:

• На полдник — for an afternoon snack
• бабушка — grandmother
• дала — gave
• детям — to the children
• по одной ватрушке — one vatrushka each

Russian word order is flexible, so other orders are possible, for example:

• Бабушка дала детям по одной ватрушке на полдник.
• Детям бабушка дала по одной ватрушке на полдник.

These versions would shift emphasis slightly, but the core meaning stays the same because the cases show the grammatical roles.

The original sentence sounds very natural, with На полдник setting the scene first.

Yes — that is a very good natural English translation.

Other good translations include:

• For afternoon snack, Grandma gave the children one vatrushka each.
• Grandmother gave the children a vatrushka each for their afternoon snack.
• Grandma gave the children one cheese pastry each for a snack.

The exact English wording can vary, but the important parts are:

• бабушка дала = Grandma/grandmother gave
• детям = to the children
• по одной ватрушке = one each
• на полдник = for an afternoon snack

Usually grandma is the more natural choice in everyday English, because бабушка is a warm, ordinary family word.

• бабушка → grandma / grandmother

In many contexts:

• grandma sounds more natural and conversational
• grandmother sounds a bit more formal or neutral

So both are correct, but grandma often matches the tone better.