Recording Classroom Lessons

Bantymom

New member
Hi! *waves*

Newbie here, but I have found that forums are the absolutely BEST place to get real information, so I've joined here hoping it will work out again. I know nothing about microphones or mic stands

Why is this post so long? Wanted to provide as much information from my side as I could right up front. I appreciate your patience in reading this.

Situation: I need to record Mathematics lessons in various classrooms. For this, I have been supplied with an iPad, which seems to do a serviceable job of recording the video. However, when recently viewing a similar video taken by another teacher, it was clear that the mic on the iPad was barely capable of picking up what the teacher was saying, but it was nearly impossible to hear the students.

So I'm looking for a microphone that could help; one that would pick up the sounds that a person sitting in the room would hear.

Audience: These video recordings are for teachers to view, either individually on their own devices or as a group in a Professional Development training, where the video would be projected on to a screen to about 6-20 teachers at a time.

And did I mention I'm a teacher? I can't afford the best thing out there. I know I can't do this on the cheap, but I don't have a Hollywood budget either. Have mercy.

Considerations:
1) I do not have my own room, but go from room to room supporting teachers, so I can't set up any kind of permanent system. Whatever I use needs to be portable.
2) I might have to shoot the video from a back corner of the room, but if there were a fairly easy way to do so, I might be able to get a mic closer.
3) An Alvoxcon 20 Wireless Mic was suggested, but it seems to be one you would have to hold right up to the speaker, which will not work. I work with 1st-grade and Kindergarten classrooms and passing around a mic would be very distracting to the lesson.
4) As much as I would love to find a way to suspend the mic above the students, most likely it would end up being behind the students.
5) I need to find a way to support the mic in one place where it can pick up the teacher and the students, just the way a person in the room would be able to hear them, so specific suggestions for a lightweight mic stand would be very helpful.
6) It would be best if I didn't have to connect the mic directly into the iPad (thought that is not a deal breaker), so is wireless possible?

Since I don't even know what I'm talking about, I have probably missed some important information. Just let me know and I will do my best to supply it.

Edit: Just read something about a "shotgun mic" which looked like it gets mounted on top of a camera and so points to what is being shot, but doesn't have to be in the speakers faces. Is this kind of thing a possibility if I were to set to the side of the lesson and point it toward the group from the side? I'm sure that isn't clear. Imagine the teacher at the board and the students on the carpet on the floor facing her. Would a shotgun mic work set up on the side of that situation and pointing in?

Thank you for any help you can give me,

Bantymom (microphone newbie)
 
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Behind the students is likely the least optimum placement.

Since you teach mathematics you might have an advantage understanding some of the physics and geometry of sound. Sound radiates as a three dimensional field so it obeys the inverse square law. Doubling the distance quarters the strength of the signal. Combine that with the issue of direct versus reflected sound and you confront what's known as critical distance, the distance from the source where reflections overwhelm the direct path of the sound and degrade clarity too much.

Microphones don't hear like human ears. We (most of us) have two ears and sophisticated processing to detect the desired signal from a mix of sounds that arrive at our ears. A microphone defeats that function. The solution is proximity. Get the mic close to the source. Many mics have some directionality to them to give you a bit more flexibility, but getting close is always helpful in adverse acoustic environments.

Voices are directional. Placing the mic in front of the speaker will be better than behind.

This might be a case for using two mics, one on you and one facing the students. Ideally, capture the two signals on separate parallel tracks so you can balance them after the fact.
 
Hmm? Tricky. If you possibly can look at a BBC TV programme called "Question Time". This is a panel of mostly politicians with an MC seated centrally. The pickup of MC and polys is very good (MC would be you!) as they have a dedicated microphone.

However, when they take questions from the floor they use a roving boom mic and even then the pickup is often poor and you often miss the audience member's first words as the sound guy scrambles to boost the gain! If, with their resources and vast experience this is the best the BBC can do I think capturing student contributions is going to be very tricky. Can you have a spare bod operating a mic on a stick?

These are my first thoughts. I must go back and read your piece again more carefully. Old, meds y'know.

Dave.
 
"Professional Development training," Again, hmm? Is that another department? If so they SHOULD know the problems you are going to encounter and not just bolt you up for the job. Freak! They should TRAIN you! And know the equipment you need and what it will cost.

Recording yourself is not that difficult. A tie tack radio mic is not cheap but there really is no other way if you are moving about a black or white board. You then really need to get the student's sounds onto another track and all needs to go into a dedicated sound recorder where it will be edited and married up with the video by the AV experts in the Training Dept!

Google the products of the Zoom company.

Found this for thee..SubZero SZW-30 Dual Lavalier and Headset Wireless Microphone System at Gear4music

I dare say you can find something similar but I have no idea of the quality and you have to be wary of the local laws relating to radio mics.

Dave.
 
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One or two boundary mics - the very last thing you want is shotguns because they need aiming. If the student on row 10 has a quiet voice, tough - it just won't work without a mic runner. For a simple best and cheapest result - a couple of budget boundaries = maybe $40 for cheap Chinese or up in the hundreds for Bartletts - will be the best you can get without a dedicated operator - and probably real time editing afterwards. Microphones are also the killers of free-speech in education. The impact of a visible microphone can change group dynamics drastically - one of the things I looked at in my PGCE many moons ago.
 
This might be a case for using two mics, one on you and one facing the students. Ideally, capture the two signals on separate parallel tracks so you can balance them after the fact.

This is what I was thinking as I was reading the OP's post. One mic is a lavalier clipped to the lecturer, the other mic is a shotgun on a mic stand pointed to the classroom. Some editing afterwards to remove room noise when the students are not asking questions.

At first, I thought a simple audio interface with 2 channels would suffice. But on second thought, a field recorder like the Tascam DR40 (which I bought recently) might be better for setup and budget reasons.. With that, you could point the built-in mics towards the room and use an external connector for the lavalier. No need for a shotgun mic, just the one lavalier. Then some simple audio editing to remove unwanted room noise when the students are not asking questions.
 
A couple of boundary mics (per [MENTION=178786]rob aylestone[/MENTION]) mixed and piped directly into a camcorder with a stereo mic input jack will probably do a better job than anything you can reasonably rig up with a phone/tablet IME.

With a field recorder you could also include a wireless mic on the teacher, but there's some latency to deal with that makes setting that up for a simple capture of audio direct to video usually less than perfect. (Adding a time/clock sync and then sending the video and audio independently to another device for capture can work if the field recorder supports adjusting for latency on individual inputs.)

Of course, a better way would be for the speaker to have a wireless mic (lav/face) with a couple boundary mics and then some guy scurrying around with a shotgun on a pole to capture questions, and someone to stitch it all together in post [production].
 
What intrigues me is that most UK colleges and universities would just arrange for a technician to record the session. That's pretty common in universities as standard practice for lectures in case people are not there. In presumably school or college, and you are recording a maths class, then visuals are far more critical than say in a history class. Not sure how you teach maths, but formulii, diagrams, graphs, equations and other everyday stuff involves writing. Would a video camera not be more useful than sound only? Schools with visually impaired students often have big issues with maths because of the difficulty with not seeing things written down,
 
Wow! I knew I could count on a forum for help!

I can't digest all of it right now, and I don't want any of you to think that I am ignoring your suggestions. I just have to meet with our director of assessments and then go to our coaching forum, so I can't read all of this amazing information carefully right now. I will do so after work.

However, let me clear up a few things:

I'm not at a university. I'm just an instructional coach at an incredibly underfunded elementary school district (preschool-6th grade) on the poor side of town.

There is no "Professional Development Department," and those higher than I don't know anything much more about this than I. We Instructional Coaches are the Professional Development Department, lol! Our expertise is in subject content, lesson delivery, and classroom management (4-year-olds to 12-year-olds)

We do have in IT department (hardware/software) and an EdTech department (teaching tech-phobic teachers to teach tech to students) EdTech suggested the hand-held mic. I've put in a help ticket to IT, but they've not replied yet. It might take a week or so (they have to keep the tech running at all 12 schools, so I'm not high on the priority list, which is fine, students and classroom teachers need them more than I)

I wish, really really wish, we had a person who would just come out to do the recordings with all the right equipment, but as I said, the district answer was to give the instructional coaches iPads.

What kind of mic does an iPad have? It seems to pick up all the sound, just not loud enough because the person recording has to be too far away. Could I somehow use two iPads? One for video and one for sound?

We might have a tie-tack/lavalier mic I can use for the teacher/me. I also think I might be able to suspend a mic from a light fixture (like I've seen done for choirs).

I have no sound mixing equipment other than iMovie and maybe GarageBand? (I've never used that)

Thank you all again. I will read everything again more closely tonight. I'm getting excited!
 
How do the IT hopeless/technophobes cope? My experience is that many excellent teachers cannot change a lightbulb? They're lucky they have you!
 
Bantymom,
I too provide professional development. For our 77 ISDs and 67 Charter schools, in our 10-county Region, we have Iris Connect with Swivl[tm] systems, for our school districts to borrow, that do exactly what you are attempting. It has two tripods, one for a stationary iPad, and the other tripod rotates a second iPad 360 degrees, to follow a fob/ microphone that is worn by the teacher. Google it and put one on your wish list. They are slick.

Now my poor man's solution that I think may work for you..... Get a free ZOOM webinar account. It will let you conduct a MP4 rendered-webinar, for up to 45mins (on the freebie acct), that you will join with your iPad and smart phone. Think Skyping with yourself..... ZOOM will let you record the session and render a MP4 video with all sounds captured.

Set the iPad to video capture your subject, video On, mic muted. Then, using your smartphone as a lavaliere in your pocket, you can leave the video off, and mic On. You will have to toggle the settings in ZOOM, to turn off "spotlight the speaker" so that your audio feed will not be the only screen recorded. If there is enough distance between devices, you might be able to turn both mics ON, on the phone and iPad, with their volumes muted, and not get a feedback loop. I have not experimented with that. May be something you can play with this weekend.
Dale
 
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Bantymom,

DaleVO seems to know his shallots, cultivate him!

I shall bow out from the discussion unless a basic technical, wires and stuff, query comes up. I am too far away and my experience is from long ago with blots on stage at Am Drams (freaking nightmare with their weedy little voices! "Never work with animals....SO true!)

I really feel for you tho', been thrown to foxes if not quite wolves IMHO. DO push for the gear Dale suggests. It seems "institutional sound" always gets the short end of the budget stick BOTH sides of The Pond.

Dave.
 
Had to come back...There is a thread started about a week ago at sos.com of a similar "delegation".

A teacher again and this time tasked with installing a PA system in a gymnasium! Now even the seasoned PA pros here would baulk at THAT job! The acoustics are going to be horribly echoey and the placing of sound treatment very tricky. The gear, especially speakers will have to be protected from ballistic bodies and other projectiles. The teacher has not so far come back with exact details but has been advised to get in expert advice. Won't be the money for that of course!

#You gotta know when to hold'em, know when to fold 'em. Know when to walk away and know....#!!

Dave.
 
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