I'm usually test-driving electric cars, but lately I've been playing with a fun alternative: a clip-on electric motor that converts an ordinary bicycle into an e-bike.

Why it matters: CLIP is billed as a common-sense solution for urban commuters, making it easier for people to switch from driving to bicycling for short trips.

• With pedaling assistance from a simple friction drive system, it's less complex and a lot cheaper than a fully electric bike.

Zoom in: Half of all urban trips are 3 miles or less, which is CLIP's target market.

• These commuters don't need a powerful e-bike with lots of range — they just need a little extra oomph for the occasional hill, say CLIP co-founders Som Ray and Clement de Alcala.
• For many commuters, an e-bike is over-engineered and expensive, they argue, with prices ranging from around $1,500 to $5,000.
• CLIP's "plug & play" device, starting at $499, offers many of the benefits of an e-bike at a fraction of the cost.

What they're saying: "What we really want to do is make it easy for people to ride every day for their commute to reduce emissions," de Alcala tells Axios.

• "There are 100 million bikes in circulation in the U.S. Why not make them more convenient to use each and every day?"

How it works: The slickly designed device has a spring-loaded clamp that attaches to the forks of the bike's front wheel, just below the brake calipers.

• Propulsion is provided when the unit's roller comes in contact with the front tire, matching the torque of the wheel up to 15 miles per hour.
• A Bluetooth controller that attaches to the handlebars provides an added boost at the push of a button. A second button acts as a digital brake and can recharge the battery on downhill glides.

By the numbers: CLIP provides 6 to 18 miles of range, depending on the battery size, and recharging takes less than an hour.

• It's available in two models: the $499 Commuter, with a 98 Wh battery, and the $599 Explorer, with 192 Wh.

💬 My thought bubble: CLIP is a brilliant idea and makes sense for short jaunts around town.

• I tested the Explorer model and used it to bike to church and to a couple of meetings, and didn't feel sweaty or out of breath when I arrived.
• I felt the CLIP's pull at the very beginning of my ride as the mechanical roller synced up with the bike's tire, but most of the time I was pedaling at a steady rate in "auto-roll" mode.

If I got tired, or had to ride uphill, I pressed and held the remote button on the handlebars to accelerate effortlessly.

• The unit I tested weighs just under 10 pounds and is not difficult to attach, but takes a little practice to get it right.
• I like that you can detach it and carry it by the handle or in a backpack.
• There are other DYI e-bike conversion kits, but CLIP is simple to attach or remove without any tools.

Yes, but: My family has four bikes in the garage, and the only one it would fit was a 40-year-old Motobecane racing bike that's gathering dust on the wall.

• The forks on the other bikes were too thick, or have a shock-absorbing suspension on the front wheel, so the company loaned me a tester bike as well.
• CEO Ray tells me the CLIP is designed to fit most basic urban commuter bikes — including rental bikes — but the company is working to expand the line for other types of bikes.

What's next: CLIP wants to democratize access to e-biking worldwide, and plans to pilot a $100 version in India later this year.

• It's also developing a vending machine concept that would allow people to rent a CLIP along with a bike.

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Classrooms nationwide need more cooling during back-to-school season now compared to past decades, a new analysis finds.

Why it matters: Maintaining a comfortable and healthy environment in schools is key to kids' educational success, but that's getting harder amid a warming climate.

• Many schools are already making adjustments — some in the Austin area, for example, have shifted recess earlier and are limiting kids' outside time, Axios' Nicole Cobler reports.

Driving the news: A Climate Central report finds that cooling demand between late July and early September increased in 95% of nearly 250 U.S. locations analyzed between 1970 and 2023.

• The nonprofit climate research group's analysis is based on a metric called "cooling degree days" (CDD), which measures the difference between a location's daily average outdoor temperature and 65°F — "considered the ideal indoor temperature," per the report.
• "For example, a day with an average temperature of 90°F has 25 CDD (90°- 65°)."

What they did: To get annual demand, CDD was added together for every day in the 7-week time period when students typically return to school.

Zoom in: Reno, Nevada (+320%); Eureka, California (+300%); and San Francisco (+240%) saw the biggest percentage increases in back-to-school CDD between 1970 and 2023.

Between the lines: Back-to-school cooling demand was around 34% higher over the last decade largely due to human-caused climate change, Climate Central estimates.

• That's based on the group's Climate Shift Index, which seeks to measure how climate change has affected daily temperatures.

Threat level: Many schools in rapidly-warming locations also start school in mid-to-late August, when heat waves can strike.

What's next: Like other buildings, schools must adapt to a changing climate — and that can mean costly upgrades.

• "Buildings can be retrofitted with better windows and insulation to reduce energy waste, and existing fossil-fuel burning systems can be replaced with safer, more energy-efficient options," per Climate Central.

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Alex here. It was a pleasure bringing you What's Next for the last two-plus years.

• It's been especially heartwarming to get notes from many of you over the past few days about how much you've enjoyed this newsletter.

What's next: I'll still be here at Axios, writing about data, aviation and more — drop me a line anytime at [email protected], and find me on Threads at @AlexJamesFitz.

• For continuing coverage of the future of transportation, bookmark Joann's author page at Axios or follow her on X or LinkedIn. Get in touch at [email protected].