A child plans to raise money by producing and selling a calendar of community events. The child will produce 1,000 calendars which he plans to sell for $10 each. The cost of producing and marketing the calendars will be $1.50 each. The child will have to sell _____ calendars to break even.

To find the number of calendars the child needs to sell to break even, we need to consider the total cost and the revenue.

The total cost of producing and marketing 1,000 calendars is $1.50 x 1,000 = $<<1.5*1000=1500>>1500.

The revenue from selling 1,000 calendars is $10 x 1,000 = $<<10*1000=10000>>10000.

So, the child needs to sell $1500 / $10 = <<1500/10=150>>150 calendars to break even. Answer: \boxed{150}.