her lessons start at 9 o'clock vs school finishes at 9 o'clock

Some examples from the web:

• Your hit is 10 feet at 9 o'clock.
• They can be exchanged for tickets starting at 9 o'clock.
• This train gets to Chicago at 9 o'clock tonight.
• I've booked three persons at 9 o'clock there.
• Scorer noted 10 feet at 9 o'clock.
• It's been 10 days since you sleep at 9 o'clock and wake up at midnight.
• The woman's driver comes each day at 9 o'clock to take her.
• Be on the floor at 9 o'clock
• At 9 o'clock, turn off the light in Wataru's room.
• Lessons start at nine... sharp.
• You're eating paella at 9 o'clock in the morning?
• You're to see Trepossi at 9 o'clock.
• I am very sorry about this but we are going to have to stop the debate at this point and resume it at 9 o'clock this evening.
• You have to be at the endemic bank at 9 o'clock exactly.
• At 9 o'clock, there is a bus trip to Lanzhou
• Downtown-3! Give us some pressure at 9 o'clock, on my count!
• Mr President, I should like to start by saying that 15 minutes ago there were still no amendments in English to two of the reports despite your assurances at 9 o'clock that there would be some within a couple of minutes.
• You see this lady over here at 9 o'clock?
• Yesterday I left home at 7 o'clock in the morning and, because of the behaviour of Air France at Charles de Gaulle, I arrived here at 9 o'clock yesterday evening.
• We have no difficulty with the debate on the Dankert report beginning at 9 o'clock, provided we can be assured that the senior members of the administration, from the Secretary-General downwards, are here for the discharge debate on Parliament's budget.

Some examples from the web:

• Your hit is 10 feet at 9 o'clock.
• They can be exchanged for tickets starting at 9 o'clock.
• This train gets to Chicago at 9 o'clock tonight.
• I've booked three persons at 9 o'clock there.
• Scorer noted 10 feet at 9 o'clock.
• It's been 10 days since you sleep at 9 o'clock and wake up at midnight.
• The woman's driver comes each day at 9 o'clock to take her.
• Be on the floor at 9 o'clock
• At 9 o'clock, turn off the light in Wataru's room.
• You're eating paella at 9 o'clock in the morning?
• You're to see Trepossi at 9 o'clock.
• I am very sorry about this but we are going to have to stop the debate at this point and resume it at 9 o'clock this evening.
• You have to be at the endemic bank at 9 o'clock exactly.
• At 9 o'clock, there is a bus trip to Lanzhou
• Downtown-3! Give us some pressure at 9 o'clock, on my count!
• Mr President, I should like to start by saying that 15 minutes ago there were still no amendments in English to two of the reports despite your assurances at 9 o'clock that there would be some within a couple of minutes.
• You see this lady over here at 9 o'clock?
• Yesterday I left home at 7 o'clock in the morning and, because of the behaviour of Air France at Charles de Gaulle, I arrived here at 9 o'clock yesterday evening.
• We have no difficulty with the debate on the Dankert report beginning at 9 o'clock, provided we can be assured that the senior members of the administration, from the Secretary-General downwards, are here for the discharge debate on Parliament's budget.
• Debating one of the most important acts of legislation for two years, at 9 o'clock at night before rows of empty seats, is frankly unworthy of a Parliament and I would like you to mention this fact to our President.